By MICHAEL FALCONE ( @michaelpfalcone ) and AMY WALTER ( @amyewalter )

DES MOINES - With just four days to go until the Iowa caucuses, there are fresh signs today that Mitt Romney and Ron Paul are solidifying their positions at the front of the pack. What that means is that the race for the "best of the rest" is getting fiercer by the day.

The campaign trail attacks among Rick Santorum, Rick Perry, Newt Gingrich and Michele Bachmann are taking on new urgency as the four contenders play a game of political musical chairs, rotating spots in third, fourth, fifth and sixth place in Iowa polls out this week.

Today's NBC News-Marist University gave Romney top honors with 23 percent support followed by Ron Paul at 21 percent. But underneath them, there's Rick Santorum who's garnering 15 percent of the vote, Rick Perry (14 percent), Newt Gingrich (13 percent) and Michele Bachmann (6 percent).

Perry moved up one place compared to a CNN-Time Magazine poll of Iowa Republicans released earlier this week, Gingrich moved down once space and Bachmann remains at the very bottom.

One big question to come from the new numbers: Is Perry poised for a good caucus night? His position shows him with room to grow and Iowans this week are getting their fill of the Texas governor on the airwaves. (If you're in Iowa, just turn on the television. It won't be long before you see a Perry ad pop on the screen.)

Santorum and Perry dueled on the trail yesterday after Perry came out swinging against the former Pennsylvania senator in a new radio ad. At one of his campaign stops yesterday Perry attacked Santorum by name for being a "prolific earmarker" during his career in Congress.

"I love Iowa pork, but I hate Washington pork, and Senator Santorum he loaded up his bills with Pennsylvania pork," Perry said Thursday at the Coffee Corner in Washington, Iowa.

The radio spot, which is airing in Iowa, picked up the candidate's line of attack, drawing attention to Santorum's support for such controversial projects as the Alaska "Bridge to Nowhere." http://abcn.ws/sPkWaO

Meanwhile, a super PAC supporting Santorum is coming to his defense, putting a television ad on Iowa airwaves touting his conservative credentials.  "All across Iowa there's a principled Conservative uniting Republicans," the ad says over video of Iowa and photos of Santorum and voters. http://abcn.ws/u9CVqg

And Santorum, who has not found himself on the receiving end of attacks from his rivals until this week, turned Perry's criticism right back on him, asserting that "Perry hired people to earmark funds for Texas."

"I don't have a perfect record, but I have a pretty darn good one and the reasons I did what I did, if I made a mistake I admit it, but if I think I did the right thing, I'm going to stand up and fight for the things I believe in," Santorum said in Davenport, Iowa last night. http://abcn.ws/uAjhfq

Gingrich, who just a few weeks ago was on a short-lived but meteoric rise to the top of the Republican field, now has to contend with the new realities of being in the middle of the pack.

"I'm very satisfied with where we are," Gingrich said in Western Iowa yesterday. "Look it's all going to be just turmoil until Tuesday night."

And as ABC's Elicia Dover reports, Gingrich said there will be room for more than three tickets out of Iowa and even if he finishes fourth, he will remain in the race: "Considering I'm more than 20 points ahead in some states, it would be fairly foolish me not to stay in the race."

BOTTOM LINE: The best thing going for Romney is the thing that has helped him all along: A divided conservative base that can't or won't coalesce around one anti-Romney candidate. Today's NBC News-Marist poll and Gallup national polling both show that. Plus, Romney's biggest threats in Iowa - Paul and Gingrich - are also the most polarizing candidates even among GOP caucus voters.

While Perry and Santorum have the most room to grow, both have the most difficulty carrying that momentum to New Hampshire. A recent CNN poll in New Hampshire showed a whopping 59 percent of likely primary voters saying that they wouldn't consider supporting Perry. Meanwhile, Santorum was commanding just 4 percent of the vote in the Granite State. Still, Perry and even Santorum could look forward to a stronger showing in South Carolina.

THE ANTI-NEWT SHOW. ABC's Z. Byron Wolf reports: "How total was the airwave pile on Newt Gingrich this month? Half the ads in Iowa had a Gingrich focus. And the vast majority were negative, per a new analysis from the Campaign Media Analysis Group, which tracks the television ad wars. They calculate that 45 percent of the ads aired in Iowa were anti-Newt this month.  Only one in five negative ads were directed at Mitt Romney. 'The difference between Romney's situation and Gingrich's is that many of the attacks on Romney were glancing blows delivered in ads that attacked multiple candidates,' said CMAG's Ken Goldstein. 'Ads attacking Gingrich tended to be solely and completely focused on him.'"

DEMOCRATIC COUNTER-PROGRAMMING. The Democratic National Committee is out with a new web video this morning putting pressure on Mitt Romney to release his tax returns. Their message: "Just what is Mitt Romney hiding?" Here's the memo from the DNC accompanying their video: "If the practice of making tax returns public was good enough for Mitt Romney's dad and every other major GOP candidate for president for the past 40 years to follow the practice, why isn't it for Mitt Romney? Perhaps because it would show that on the millions of dollars in income he enjoys each year, Mitt Romney pays a lower tax rate than teachers, fire fighters, police officers or other middle class wage earners." WATCH: http://bit.ly/vKFQPq

 

DON'T KNOW MUCH ABOUT THE IOWA CAUCUSES? "The Iowa caucuses will award no delegates to any candidate, and they follow a complicated delegate-selection process. But the Iowa caucuses are significant for two reasons: timing and tradition," reports ABC's Chris Good. "The caucus has a mixed history when it comes to choosing the eventual nominee of both the Republican and Democratic parties. Five Democratic winners - Jimmy Carter, Walter Mondale, Al Gore, John Kerry and Barack Obama - along with three Republican winners - Gerald Ford, Bob Dole and George W. Bush - have parlayed their Iowa victories into Democratic and Republican presidential nominations since 1972. But where the event truly gains its importance is in terms of momentum. … In presidential voting, the Iowa GOP caucuses are essentially a statewide straw poll. The Hawkeye State will send 28 delegates to the Republican National Convention in Tampa Aug. 23, out of 2,286 voting delegates total, but all of Iowa's delegates will be 'unbound,' or free to vote for any candidate for president or vice president."

  So when caucus-goers show up Jan. 3, what will they actually vote for? And how do the caucuses work? More from ABC's Iowa caucus primer: http://abcn.ws/uzHwdR

PRIMARY COLORS.

-Rick Santorum is proving once again that he's one of the hardest working candidates in presidential politics. ABC's Shushannah Walshe notes that his town hall last night in Davenport, Iowa two hours long and he stayed for another 30 minutes shaking hands. This is the kind of in-depth access to candidates that Iowans demand and Santorum's delivering.

-Mitt Romney yesterday made three stops on his bus tour through Iowa, the cutest moment by far was when an 8-year-old boy in Mason City asked him if it is "hard to run for the president." Romney gave a candid response, telling the young man that sometimes it is hard to stay in a different hotel every night, but advised the boy that if he given the chance, he should do it - win or lose. http://abcn.ws/rA6y5c

-Michele Bachmann sang "God Bless America" and cut a cake in Nevada, Iowa yesterday to celebrate the end of her whirlwind 99-county bus tour. -ABC's Russell Goldman

-ABC's Jason Volack, who is on the campaign trail with Ron Paul, notes that "the further we moved away from Des Moines, the larger the crowds grew yesterday. He attracted about 100 people at the first event in Perry, about 150 in Atlantic, and a whopping 750 people in Council Bluffs."

THE BUZZ

  RON PAUL CALLS IRAN SANCTIONS AN 'ACT OF WAR.' "Unwilling to back down from the growing criticism that his foreign policy would be 'dangerous,' Ron Paul told voters in Iowa that western sanctions against Iran are 'acts of war' that are likely to lead to an actual war," ABC's Jason Volack notes. "Paul said that Iran would be justified in responding to sanctions by blocking the Straits of Hormuz, adding that the country blocking the strategically important strait is "so logical" since they have no other recourse. He then compared the situation to China blocking off the Gulf of Mexico to trade. 'I think the solution is to do a lot less a lot sooner, and mind our own business, and we wouldn't have this threat of another war,' Paul said. Paul made the comments to a crowd of 100 people in Perry, Iowa, the first stop on his two-day campaign swing through the western part of the state." http://abcn.ws/sF7irD

NOTED: Ron Paul got sort of a backhanded celebrity endorsement today from pop idol Kelly Clarkson. The diva tweeted Wednesday morning "I love Ron Paul. I liked him a lot during the last Republican nomination, and no one gave him a chance. If he wins the nomination for the Republican Party in 2012, he's got my vote. Too bad he probably won't." The tweet apparently drew quite a response on Clarkson's Twitter feed as she responded to fans complaining about racist comments published years ago in newsletters published by Paul. http://abcn.ws/v2XMuQ

ROMNEY PORTRAYS OBAMA AS OUT OF TOUCH. A dispatch from the Huffington Post's Jon Ward in Mason City, Iowa:  Mitt Romney on Thursday sought to portray President Barack Obama as out of touch with the struggles of everyday Americans - a charge he himself has often faced - by comparing the president to a former French queen who was overthrown during the French Revolution. "When the president's characterization of our economy was, 'It could be worse,' it reminded me of Marie Antoinette: 'Let them eat cake,'" Romney said, referring to the infamously dismissive remark toward the poor attributed to the queen. "This is not a time to be talking about, 'It could be worse.' It's a time to recognize that things should be better," Romney said during an interview on his campaign bus with The Huffington Post. "And the president's policies have failed the American people, have led to 25 million people still being out of work. He didn't cause the recession, but he has made it deeper and has made the recovery more tepid and the pain last longer." http://huff.to/tluhKy

SUPER PACS GO 'STEALTH.'  "Super PACs spending millions of dollars on the brutal ads shaping the GOP presidential primary have taken advantage in the last few weeks of a pair of loopholes that will let them keep their donors secret until after votes are cast in the first four big contests," Politico's Ken Vogel and Dave Levinthal report. "Some of these new groups backing Mitt Romney, Newt Gingrich and Jon Huntsman wrote short letters this month to the Federal Election Commission requesting a bureaucratic change that lets them delay revealing their funders, while super PACs supporting Rick Santorum and Rick Perry are benefiting from a longstanding, but little-noticed, ruling that exempts their Iowa caucus ads from disclosure requirements. The loopholes are the latest development in a campaign that has seen an explosion of unlimited spending that's difficult to trace. And exploitation of these loopholes likely guarantees that voters won't find out who's paying for a majority of primary campaign ads until late on the night of Jan. 31. That's after polls have closed in states expected to go a long way towards determining the GOP presidential nominee - the Iowa caucuses and primaries in New Hampshire, South Carolina and Florida." http://politi.co/u8X88e

GOP FIELD TAKES BROAD VIEW OF PRESIDENTIAL POWER. "Even as they advocate for limited government, many of the Republican presidential candidates hold expansive views about the scope of the executive powers they would wield if elected - including the ability to authorize the targeted killing of United States citizens they deem threats and to launch military attacks without Congressional permission," The New York Times' Charlie Savage reports. "As Republicans prepare to select their party's 2012 presidential nominee, Newt Gingrich, Jon M. Huntsman Jr., Ron Paul, Rick Perry and Mitt Romney have provided detailed answers about their views on executive power in response to questions on the topic posed by The New York Times, which is publishing the full text of their responses online. The answers show that most of them see the commander in chief as having the authority to lawfully take extraordinary actions if he decides doing so is necessary to protect national security. Only Mr. Paul, the libertarian-leaning congressman from Texas, argued for a more limited view of presidential power." The responses: http://nyti.ms/rBiJTn

WHO'S TWEETING?

@ postpolls : Top "not acceptable" candidates in  #nbcmaristIowa poll amy likely voters: Gingrich 35, Bachmann 34, both far higher than Romney or Santorum

@ JenniferJJacobs : Iowa voter, skeptical of  @MittRomney's answer about bipartisanship: "It's all sunshine and puppy dogs."  dmreg.co/sqIvMK  #iacaucus

@ bkappcbs : On Romney's cold weather event, Iowan inside the Hyvee says "I like him but I don't like him that much."

  @ JillDLawrence : Have Romney's rivals given up on denting him?  @Roarty_NJ on his absence from circular firing squad  bit.ly/tPx47s  @nationaljournal

  @ TheLloydGrove : Rick Santorum surging into Iowa relevancy at just the right moment as the latest anti-Romney  thedailybeast.com/articles/2011/…

GOOD MORNING IOWA. Don't forget to check The Note blog every morning for the latest edition of "Good Morning Iowa" - a one-stop-shop tip-sheet covering everything you need to know from the Hawkeye State, reported by ABC's Shushannah Walshe.

DISPATCHES FROM THE TRAIL. Also, keep an eye on our new political website OTUSNews.com ( www.Otusnews.com) The Note ( http://abcnews.go.com/blogs/politics/the-note/) and on ABC News/Politics ( http://abcnews.go.com/politics) for rapid-fire updates from the campaign trail between now and the Iowa Caucuses. Follow our reporters in the field on Twitter:

Michele Bachmann : ABC's Russell Goldman ( @GoldmanRussell )

Newt Gingrich : ABC's Elicia Dover ( @EliciaDover )

Jon Huntsman and New Hampshire: ABC's Susan Archer ( @TheOnlyArcher )

Ron Paul : ABC's Jason Volack ( @Jason_Volack )

Rick Perry : ABC's Arlette Saenz ( @ArletteSaenz )

Mitt Romney : ABC's Emily Friedman ( @EmilyABC )

Rick Santorum and Iowa: ABC's Shushannah Walshe ( @shushwalshe )

 

Check out The Note's Futures Calendar:  http://abcn.ws/ZI9gV

 

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