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

As President Obama takes to the Rose Garden this morning to urge Congress to pass the American Jobs Act, eight of the Republicans seeking to replace him will gather in Florida for their second debate in less than a week.

ABC’s Jake Tapper reports that the president will announce he’s sending the jobs bill he outlined last week to Congress. And Tapper notes that Obama will be joined today “by people from across the country who would benefit from the American Jobs Act, including teachers, police officers, firefighters, construction workers, small business owners, and veterans.” http://abcn.ws/r3BL3K

President Obama is expected to speak at about 10:30 a.m. ET.

And while Obama is talking jobs, the topic du jour at tonight’s CNN/Tea Party Express debate in Tampa, which starts at 8 p.m. ET, is likely to be Social Security. With a front-runner Rick Perry touting his “Ponzi scheme” line almost everywhere he goes, several of his rivals are planning to pounce.

For starters, there’s Michele Bachmann, who was largely relegated to second-tier candidate status at last week’s debate at the Ronald Reagan Presidential Library in Simi Valley.

“Bernie Madoff deals with Ponzi schemes, not the grandparents of America,” a Bachmann adviser told the Washington Examiner’s Byron York. “Clearly she feels differently about the value of Social Security than Gov. Perry does.  She believes Social Security needs to be saved, that it’s an important safety net for Americans who have paid into it all their lives.” http://bit.ly/okK8JV

In addition to Bachmann, look for rival Mitt Romney to step up his attacks on Perry over Social Security and other issues. Romney and his advisers have been pushing the notion that Perry’s dim view of the entitlement program makes him unelectable in a general election.

Also likely to be on the agenda on the debate stage tonight: immigration. As the Boston Globe notes, Perry’s ” long record on the issue, amassed over 11 years as governor, is offering fodder for critics on the right as well as political rivals, who see immigration as one way to drive a wedge between the Texas governor and the conservative voters who hold considerable sway in the primary.”  http://bo.st/p599ST

This is exactly the kind of terrain on which Democrats would love to be able to conduct the 2012 campaign: the GOP candidates in a food-fight over Social Security  and other issues while President Obama keeps his focus on jobs and the economy.

However, special election campaigns for House seats in Nevada and New York (more on those below) are showing the limits of Social Security as a political life-line for Democrats. In both Nevada’s 2nd Congressional District and New York’s 9th, the Democratic candidate has tried to make the race a referendum on entitlements.

But polling in both races shows the Democrat losing — a signal that frustration over the state of the economy and Washington in general is a stronger motivator for voters.

TIM PAWLENTY BACKS ROMNEY. Minnesota Governor Tim Pawlenty, who as a presidential candidate dubbed the health care plan Mitt Romney passed in Massachusetts “Obamneycare,” has endorsed his former rival today. What’s more, Pawlenty will serve as a national co-chair of his campaign. Pawlenty’s endorsement is a sign of  a growing rift among Republican primary voters between those who are attracted to a candidate who engages the base vs. one who they think can win a general election. “Mitt Romney is fighting for the same things I fought for as governor and during my campaign for president,” Pawlenty said in a statement. “As a former blue state governor, I appreciate what Mitt was able to do in Massachusetts. He created jobs and balanced his budgets without raising taxes – even with an over eighty percent Democrat legislature. That ability to get things done is what we need in our nominee. In addition, he has a background which is unmatched — his understanding of the private sector proves he knows how jobs are created which will be critical in turning our economy around. I am proud to endorse his candidacy for president of the United States.”

TPAW BACKSTORY. ABC’s John Berman reports: “On Friday Sept. 2, Tim Pawlenty and his wife flew to New Hampshire and spent the day — and night — at the Romneys’ Wolfeboro lake house. Romney asked for the endorsement then, and a few days later, Pawlenty agreed, based on his view that Romney was the best candidate to lead on the economy.”

DEBATE DEETS. CNN’s Wolf Blitzer will anchor the two-hour event, which will take place on the Florida State Fairgrounds at 8 p.m. ET. From CNN: “The debate will focus on a wide-range of topics, including the role, size and scope of government, with a specific emphasis on issue number one to tea party members and all Americans: the economy. In addition to questions from Blitzer, audience members inside the debate hall, made up in part by members from tea party groups in 31 states and the District of Columbia, will be invited to ask questions directly to the candidates. Questions will also be taken live from tea party members at debate watch parties in Phoenix, Ariz.; Cincinnati, Ohio; and Portsmouth, Virginia.”

ON TODAY’S “TOP LINE. ABC’s Rick Klein and Amy Walter interview former Secretary of Health and Human Services Tommy Thompson, who is a potential candidate for a U.S. Senate seat in Wisconsin. Also on the program, Republican businessman and former GOP presidential aide Fred Malek. Watch “Top Line” LIVE at 12:00 p.m. Eastern.  http://abcn.ws/toplineliveabc

TWO RACES WITH BIG IMPLICATIONS. “Democrats are facing the very real possibility that a pair of special elections on Tuesday will shake the foundations of the 2012 political landscape,” notes the National Journal’s Jessica Taylor. “The party is at serious risk of losing a House race in New York City that few thought would be close, and campaign officials are already close to writing off a Nevada House race they had once hoped to contest. If Republicans win both contests, it would raise fresh concerns about President Obama’s drag on down-ballot Democrats and the party’s ability to keep its Senate majority. The losses would also raise questions about whether the party can gain the 24 seats it needs to regain the House. In the last week, the race for former Rep. Anthony Weiner’s seat has given Democrats the biggest headache. The Democratic Congressional Campaign Committee late last week poured in $500,000 in a last-gasp attempt to hang onto a seat that has been in Democratic hands for decades. Before Weiner represented the Queens- and Brooklyn-based district, it was the home turf of now-Sen. Chuck Schumer, D-N.Y. … In the Silver State, the situation isn’t as ominous, but Democrats have all but written off contesting a Republican-leaning seat in rural Nevada that once seemed squarely in play weeks ago. The Democratic nominee is state Treasurer Kate Marshall, and Democrats had touted her as a leading recruit. She got off to a fast fundraising start, and hammered the Republican nominee, Mark Amodei, for supporting entitlement cuts.”

Jacqueline Kennedy’s Audio Tapes Describes ‘Our Happiest Years.’ From ABC’s Rick Klein: “Speaking just months after her husband’s assassination, Jacqueline Kennedy looked back on her time with her husband in the White House as ‘our happiest years,’ the time that she and John F. Kennedy were closest, with an extraordinary personal and political partnership thriving during the high-pressure thousand days of the Kennedy presidency.  Those recollections were part of a series of conversations the widowed first lady recorded in early 1964, in oral history interviews that mark the most detailed and personal comments she ever made on the Kennedy White House years. The tapes were kept under seal by the Kennedy Library until this month.   ABC News’ Diane Sawyer will host a prime-time, two-hour special based on the tapes Tuesday, Sept. 13, featuring exclusive, never-before-heard extended audio of Mrs. Kennedy’s oral history, rare photographs, plus an exclusive interview with Caroline Kennedy, the child of Jacqueline and John Kennedy.  The audio and transcripts of the interviews, conducted by friend and longtime Kennedy aide Arthur M. Schlesinger Jr., are being released in book form this month in ‘Jacqueline Kennedy: Historic Conversations on Life with John F. Kennedy.’” http://abcn.ws/qCapTV

@ JoshElliottABC : DO NOT MISS tomorrow night’s  @ABC special w/  @DianeSawyer examining the tapes recorded by Jackie Kennedy just after JFK’s death. 9 EDT.

THE NOTE’S INBOX:

DNC TOUTS THE JOBS AGENDA. “Today, the Democratic National Committee announced a new comprehensive effort to engage the American people in the important task of getting Congress to pass President Obama’s American Jobs Act to get more Americans back to work and put more money in the pockets of middle class Americans and small businesses.  The effort includes television ads, online ads, and a website called www.americanjobsact.com.”

FACEBOOK REMEMBERS 9/11. The White House, Bill Clinton, Sen. Chuck Schumer, Sen. Kirsten Gillibrand, Sen. Richard Lugar, Sen. Marco Rubio, Sen. John Cornyn, the White House, the FBI, DOD are among those who are encouraging fans on their Facebook pages to honor the victims of Sept. 11 by dedicating a status update. Visit the app ( http://on.fb.me/911MemorialApp) and ( http://on.fb.me/Sept11MemorialApp) to share memories and reflections.

  WHO’S TWEETING?

@ HotlineJosh : Surprise, surprise… RT  @jmartpolitico: So Tpaw was actual a center-right guy all along?

@ktumulty : GOP debate schedule is starting to feel like the movie “Groundhog Day.” Which moderator will  @Newt_Gingrich attack tonight?

@ elliottjustin : Lobbying firm boasts of relationship with supercommittee member Max Baucus’ “new wife”  bit.ly/qJ0Vid

  @ rickklein : Perry op-ed on Social Security: “Americans deserve a frank and honest discussion… we must have the guts.”  usat.ly/quCniw

@russellberman : Alternative jobs plan is tough sell for House  #GOP leaders bit.ly/pFBXha

POLITICAL RADAR: 

(all times local)

* President Obama makes remarks on American Jobs Act in the White House Rose Garden at about 10:30 a.m. ET.

* CNN and the Tea Party Express hold a Republican presidential primary debate in Tampa, Fla. Starting at 8 p.m. ET. Rep. Michele Bachmann, businessman Herman Cain, former House Speaker Newt Gingrich, former Utah Gov. Jon Huntsman, Texas Rep. Ron Paul, Texas Gov. Rick Perry, former Massachusetts Gov. Mitt Romney and former Pennsylvania Sen. Rick Santorum will participate.

The Note Futures Calendar:  http://abcn.ws/ZI9gV

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