Compiled by ABC News' Jackie Fernandez, Jayce Henderson, Amanda Van Allen and Carrie Halperin

RICK SANTORUM ABC News' Shushannah Walshe and Amy Bingham: " Inspiring Fear or Hope? Santorum's Doomsday Warning to Voters" As Rick Santorum makes his way toward a two-man race with Mitt Romney, he has ratcheted up his rhetoric , displaying an increasingly angrier tone on the stump, and painting a doomsday picture of this country that leaves his supporters with a terrifying image of the state of the nation. The former Pennsylvania senator has almost completely pivoted the focus of his stump speech from his GOP rivals to President Obama. LINK

The Wall Street Journal's Patrick O'Connor and Danny Yadron: " Santorum's Rise Brings New Attacks" Rick Santorum's rapid rise to the top of the Republican presidential field is prompting Democrats to focus increasing campaign fire on a candidate whose social conservatism, they claim, puts him outside the political mainstream. But the charges don't seem to be compelling any change of course by Mr. Santorum, who appears to relish the debate and vigorously defended his positions while campaigning Monday. LINK

The Los Angeles Times' Paul West: " For Rick Santorum voters, it's character that counts" Suburban mom Judy Dlugosielski is a liberal Republican who favors abortion rights. Yet as a crucial set of primaries nears, her choice for president is Rick Santorum, who would be the most conservative nominee of a major party in decades and a man who gained national prominence as a warrior against abortion LINK

Bloomberg's Jonathan D. Salant: " Santorum Doubles Fundraising in January" Republican presidential candidate Rick Santorum, who has emerged as the chief rival to Mitt Romney, more than doubled his fundraising after winning the Iowa caucuses last month. Romney still raised more money than all of his Republican challengers and continued to receive the most financial support from Wall Street. LINK

Politico's Kenneth P. Vogel and Abby Phillip: " Rick Santorum fundraising soared after wins" Rick Santorum rode the momentum from his Iowa caucus to pull in a $4.5 million fundraising haul last month, finishing January with $1.5 million in the bank, but also $957,000 in debt, according to a report filed Monday night with the Federal Election Commission. According to his campaign, Santorum saw another spike in donations after he swept the contests this month in Minnesota, Missouri and Colorado, though that period is not covered in Monday's report.   LINK

MITT ROMNEY ABC News' Emily Friedman: " Romney Spends Big Bucks on Media Buys, Contact With Voters" Mitt Romney raked in an impressive $6.5 million during the month of January, but public records show that the campaign has only a fraction of what it did at the start of the year still left in the bank after a month littered with expensive primaries. Romney began January with more than $19.9 million in cash on hand, but by the close of business on Jan. 31 was down to $7.7 million, having spent more than $18 million, according to financial disclosure forms made public Monday. LINK

The Hill's Jonathan Easley: " Mitt Romney campaign spending far outpaces fundraising totals" The Mitt Romney campaign fund, Romney for President, took in $6.5 million in January, but expenditures were nearly triple that amount, putting a significant dent in the campaign's cash on hand.  Romney for President's fundraising in January was down nearly $5 million from December's haul, although the first month in each new quarter has consistently been the lowest of the cycle for the Romney campaign. LINK

SUPER PAC USA Today's  Fredreka Schouten: " Financial disclosures show power of super PACs" Presidential candidate Mitt Romney's fundraising dipped to $6.5 million in January, as he struggled to fend off his Republican rivals in early voting states, according to figures released Monday evening by his campaign. Meanwhile, former Pennsylvania senator Rick Santorum, who is now leading Romney in national polls, had his best fundraising month of the campaign. LINK

The New York Times' Nicholas Confessore: " G.O.P. Campaigns Grow More Dependent on 'Super PAC' Aid" Weeks of intense campaigning in the early nominating states have left the leading Republican presidential candidates increasingly dependent on millions of dollars spent on their behalf by outside "super PACs," reports filed with the Federal Election Commission on Monday showed. LINK

The Washington Times' Luke Rosiak:  " Pro-Obama super PAC a bust in January fundraising" The big-money vehicle intended to raise astronomical sums to serve as the Democratic counter to similar action by Republican-funded super PACs and outside groups is failing miserably, federal documents filed Monday showed. Priorities USA Action, a super PAC that former top aides to President Obama left the White House last February to run, had only a single substantial donor last month, of $50,000. LINK

CAMPAIGN ADS The Washington Post's T.W. Farnam: " Study: Negative campaign ads much more frequent, vicious than in primaries past" If you thought you were living through a particularly nasty presidential primary season, turns out you were right. Four years ago, just 6 percent of campaign advertising in the GOP primaries amounted to attacks on other Republicans; in this election, that figure has shot up to more than 50 percent, according to an analysis of advertising trends. LINK

ABC NEWS VIDEOS " Santorum Makes Veiled Comparison of Obama to Hitler" LINK

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