Newt Gingrich, using a conservative conference in Washington to stake out different turf from his GOP rivals, portrayed himself Friday as the scourge of what he derisively called the “Republican establishment.”

After being introduced at CPAC by his wife, Callista, who described him as a committed family man and enthusiastic golfer, undoubtedly to deflect attention from you-know-what, Gingrich proclaimed, “This campaign is a mortal threat to their grip on the establishment, because we intend to change Washington, not accommodate it.”

This establishment, said Gingrich, who was once at its heart as the House speaker, prefers to “manage the decay” because its “timidity” prevents it from challenging the Beltway culture. He even took a shot at both parties on the Hill, saying, "Crony capitalism in Congress is fully as bad as crony capitalism on Wall Street.” The message: he is the only one promising radical change.

Mitt Romney had a very different mission. He took great pains to wrap himself tightly in conservative garb, drawing several standing ovations as he cast himself as “a severely conservative Republican governor” from Massachusetts.

At times Romney seemed to be laboring a bit too hard to ingratiate himself with the audience, saying such things as “I know conservatism because I have lived conservatism.”

While Rick Santorum, the third candidate to address the gathering, was naturally at ease with the right-wing crowd, Romney felt compelled to keep ticking off what “we” conservatives believe. Where Santorum took a series of hard shots at Romney, the former governor ignored his Republican rivals.

Santorum was the only presidential contender to take on one of his rivals, with numerous slaps at Romney. He kept returning to the theme that he is the true believer, questioning why the GOP would nominate “someone who the party’s not excited about…We need conservatives now to rally for a conservative.”

Romney’s workmanlike speech made clear that he believes he has some repair work to do with the right, especially in the wake of his triple defeat this week in Minnesota, Missouri, and Colorado.

He trotted out what is becoming a standard line, saying, “My dad grew up poor,” while adding that George Romney became the head of a car company and Michigan’s governor. His upbringing, Romney said, was “shaped by conservative values.”

Romney’s biggest applause line came when he talked about his business experience: “I’m not ashamed to say I was successful in doing it.” He also sought to put a conservative gloss on the fact that a court legalized gay marriage in the state he governed, saying he barred out-of-state gays from getting hitched there: “We prevented Massachusetts from becoming the Las Vegas of gay marriage.”

Uncorking some new attack lines against President Obama, Romney called his administration “the last gasp of liberalism’s great failure.” Santorum, who is less polished as a speaker, cast his rival as someone who doesn’t care about the poor and who created “the stepchild of Obamacare” in Massachusetts.

Santorum got a standing ovation at the end of his CPAC address, telling the audience that conservatives and Tea Party folks are not just wings of the Republican Party, “we are the Republican Party.”

The former Pennsylvania senator returned again and again to the theme that he is the true believer, saying, "We need conservatives now to rally for a conservative.”

He said Romney had “built the largest government-run health-care system in the United States,” which is not true; Romneycare, which includes a mandate to buy health coverage, still relies on private insurers and providers. But Santorum said Romney “would simply give that issue away” to President Obama. He added that the former governor “bought into man-made global warming” by adopting a cap on carbon emissions in Massachusetts.

Santorum, who exudes an Everyman persona and plays up the fact that his grandfather was a coal miner, said he want to improve the fortunes of all Americans, and “yes, the very poor.” He said he would be a champion for “blue-collar Americans, the working poor.” This was a not-so-veiled reference to Romney’s ill-chosen words on CNN that he’s not concerned about the very poor because they have a social safety net.

It was a punchy speech for Santorum, who is not a natural orator, and came as his poll numbers have shot up in the wake of his three caucus and primary victories this week.

The Catholic politician sprinkled his speech with references to religion, ripping the administration for a rule that would force Catholic organizations to include contraception coverage—“something that cost just a few dollars”—in health-care plans.

“It’s not about contraception,” Santorum said to rising applause. “It’s about liberty, it’s about freedom of speech, it’s about freedom of religion. It’s about government control of your lives, and it’s got to stop!”

While Gingrich’s delivery was relatively flat and listless, he drew a warm reception. He hit many of his stump-speech points: abolish the death tax and the Energy Department and send Ben Bernanke packing.

His one twist on the White House’s birth-control controversy was to broaden the indictment to one of his favorite targets: the judiciary.

“This administration is waging war on religion, but so are the courts,” he said.

Earlier, Santorum held forth in a hallway at a gathering called Students for Life, declaring that for him, faith provides “motivation. It’s a calling.”

His voice barely audible at the edge of a throng 10 deep, the former senator sounded an inclusive note at first, saying, “This is a movement, not based on condemnation, not based on accusation, but based on love.”

But then he pivoted to an uncompromising stance: “I don’t believe life begins at conception. I know life begins at conception.”

With Christian activist and former presidential candidate Gary Bauer standing behind him, Santorum made an impassioned pitch against abortion, saying: “We need to go out and challenge the left, which is constantly telling the public that conservatives are anti-science. The choice that they’re choosing is to kill an innocent human life.”

He mocked the contention of liberals that they want abortion to be rare, saying, “They fight every attempt to give women informed consent.”

By pouncing on religious issues, especially when the White House battle with Catholic organizations over a rule governing contraception is in the news, Santorum subtly distances himself from Romney, a Mormon, and Newt Gingrich, who converted to Catholicism only a few years ago.

Moments later, the leading faith candidate in 2008, Mike Huckabee, told the CPAC audience that he didn’t want to get hung up on ideological credentials. “I’m not so interested in hearing, ‘Mirror, mirror on the wall/Tell me who is the most conservative of all,’” he said, because all of the GOP’s candidates are more conservative than Obama.