WASHINGTON The Republican presidential race shrank to the size of a hotel ballroom Friday. Three top contenders made pitches to conservative activists gathered in Washington, each man hoping that a speech could unite a movement that months of campaigning had not.

It couldn't. But each candidate received loud ovations at the Conservative Political Action Conference.

Former Sen. Rick Santorum of Pennsylvania stressed his ideological purity. Former House Speaker Newt Gingrich stressed his courage, casting himself as an angry outsider, beset by both Democrats and his own party's establishment. Rep. Ron Paul of Texas was not scheduled to appear.

And former Massachusetts Gov. Mitt Romney - the hobbled front-runner, still struggling to stop conservatives from turning to the other two - talked about his experience.

In what could be one of his most important speeches, Romney said he'd been living the ideals of the right for decades as a businessman and "severely conservative" governor in a liberal state.

"I know conservatism," he said, repeating the word or its variants 24 times in his speech. "Because I have lived conservatism."

Santorum argued that the way to beat President Barack Obama in November was to nominate someone who was Obama's ideological opposite.

In other words: him.

"I think we have learned our lesson. And the lesson is that we will no longer abandon and apologize for the principles, and principles that made this country great, for a hollow victory in November," Santorum said.

He laid out hard-right positions on the idea of human-caused climate change (a "facade") and Obama's health-care plan. Without naming Romney, Santorum said his competitor had been less conservative on both subjects in the past.

Later, Romney told the crowd he was the only candidate in the race who had never worked a day in Washington.

Romney used his speech to underline his proposals to cut government spending, overhaul Medicare and boost the U.S. military. Echoing a message from many speakers, he said four more years of Obama would lead to debilitating debt and the erosion of American free enterprise and personal freedom.

"This is our moment. This is why we are conservatives," Romney said.

Gingrich gave the crowd an expanded version of his stump speech, which suggests overhauling the federal judiciary and abolishing the Department of Energy.

He also brought out the latest of what he called "bold proposals, which will promptly be labeled unrealistic." He wants to replace the federal civil service system with something he said would be more efficient and cheap.