WASHINGTON -- As groggy conservatives filed into the ballroom at the Marriott Wardman Park early Saturday, former Sen. Rick Santorum didn't give them much of a jolt.

Delivering the first speech of the day at the Conservative Political Action Conference, Mr. Santorum offered up a few slams of President Barack Obama, and his mention of party-switching Sen. Arlen Specter earned the requisite boos from a few thousand people in attendance. But for the most part, Mr. Santorum stuck to a sober defense of conservatism.

Emphasis on fiscal restraint and a strong national defense, he said, was lost in the George W. Bush administration, leading to Democratic control of the White House and Congress.

"Are we going to go toward European socialism or are we going to stand by these principles?" Mr. Santorum asked.

He didn't say it directly -- instead telling those in the crowd that their next step should be to back conservative candidates in Republican primary races -- but his message was clear: Rick Santorum would bring those principles to the White House.

While some of his potential rivals have been coy, Mr. Santorum has made no secret of presidential aspirations.

He has trod through the early presidential primary battlegrounds of Iowa and South Carolina, and he plans a trip to New Hampshire in April. He wrote to supporters of his political action committee, America's Foundation, last month and told them he is actively considering a run.

"It's not about, at this point, running for president," said John Brabender, a media strategist for Mr. Santorum. "It's about introducing himself to people and listening to them and finding out if it's a good idea."

Conversations with national conservative figures last week showed Mr. Santorum has hurdles to clear. First and most strikingly, he was trounced in his last campaign -- his 2006 loss to Sen. Bob Casey Jr. was the most lopsided defeat for a Senate incumbent since 1980.

"I hadn't really considered Rick Santorum as a presidential candidate," said Ed Morrissey, an influential conservative blogger for the site Hot Air. "And I think it's difficult to do that when you've lost your last statewide election. I think it's hard to argue that you're going to have a base of support going into a national election ... I think of Rick Santorum as more of an activist now."

The activist brand comes from Mr. Santorum's social conservatism: He led the fight against partial-birth abortion while in the Senate and opposed gay marriage. But across the bailout-weary nation, fiscal conservatism is ascendant. Mr. Brabender acknowledged that Mr. Santorum must emphasize fiscal matters more -- and the former senator did so in his CPAC speech.

"It's easy to get branded by some of the things you're most vocal about," Mr. Brabender said. "It would be unfortunate if he were to be singularly defined by those issues. If you look at his record, it goes much beyond that."

In a presidential campaign, Mr. Santorum could talk about legislative accomplishments and foreign policy issues, Mr. Brabender said, presenting a contrast with current and former governors Tim Pawlenty of Minnesota, former vice presidential candidate Sarah Palin of Alaska and former presidential candidates Mitt Romney of Massachusetts and Mike Huckabee of Arkansas.

Mr. Romney, Ms. Palin and Mr. Huckabee all mounted national campaigns in 2008, and Republicans tend to reward candidates who have been there before. Fred Barnes, a conservative commentator and editor of the Weekly Standard, noted that Ronald Reagan, George H.W. Bush and John McCain all ran for president in a previous cycle before earning their party's nomination.

But the 2012 field is wide open, Mr. Barnes added, and the conservative bent of Republicans in Iowa and South Carolina could tip early primaries in those states in Mr. Santorum's direction. "It's not likely, but not inconceivable," Mr. Barnes said of Mr. Santorum heading the GOP ticket.

Mr. Santorum could help his cause, said Grover Norquist, president of Americans for Tax Reform, by campaigning vigorously for 2010 candidates. Mr. Norquist said Republicans will judge potential 2012 nominees by asking: "What makes you in line to be the leader of the movement and the party? Show me scalps. Who did you elect?"

In his speech, Mr. Santorum -- who now lives in northern Virginia -- told the CPAC crowd he is fully behind Pat Toomey, the top Republican challenger for Pennsylvania's Senate seat now held by Mr. Specter, who switched parties last year. He said he regrets campaigning for Mr. Specter in 2004, against the advice of his wife.

Making little mention of social issues, Mr. Santorum attacked the spending of the Obama administration and called for a tougher stance against Iran.

He departed well before the day's keynote speaker, FOXNews personality Glenn Beck, who on his radio show earlier this month called Mr. Santorum his presidential pick. Still, Mr. Santorum's candidacy remains a long shot, even among the conservative faithful at the conference. In a presidential poll of about 2,400 attendees, Mr. Santorum came in eighth, with 2 percent of the vote. The winner: Green Tree native Rep. Ron Paul, R-Texas, with Mr. Romney in second place.

Washington correspondent Daniel Malloy writes the "Pittsburgh On The Potomac" blog exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.