WASHINGTON -- The website of former Sen. Rick Santorum's Political Action Committee, America's Foundation, states that the organization "is committed to helping candidates and causes who share Sen. Santorum's commitment to conservative principles."

The main beneficiary of the PAC's fundraising last year was Mr. Santorum's image.

In the second half of 2009, according to federal filings, the PAC raised $710,000. Of that total, $557,000 was spent on direct mail and related expenditures -- building a nationwide base of donors and supporters for Mr. Santorum. Just $38,500 was donated to candidates or causes.

"He has been committed to growing his base of supporters, folks that share his views, his conservative views," said Santorum spokeswoman Virginia Davis. "And he's doing that through direct mail, reaching out to known conservative donors."

A reason for that can be found in a letter Mr. Santorum sent to supporters in January, stating that he's considering a run for the presidency in 2012.

Pre-presidential-run PACs -- common among potential White House candidates this early in the campaign cycle -- are intended primarily to promote their founder. Donations to PACs do not count against presidential campaign limits, so the money can help fund early exploratory efforts, and if and when the candidate does form a campaign committee, he or she can go to those donors again. The PAC can give no more than $5,000 to any campaign, including the founder's own.

Mr. Santorum was unavailable to be interviewed for this story, Ms. Davis said.

His potential rivals for the Republican presidential nomination who don't currently hold political office also have active PACs.

Former Massachusetts governor and 2008 presidential hopeful Mitt Romney raised $3.57 million in 2009, and his spending was more balanced among direct mail, telemarketing and Web services. The PAC gave about $70,000 to candidates and causes.

Another 2008 candidate, former Arkansas Gov. Mike Huckabee, raised $824,000 through his Huck PAC last year, and he spent $712,000. About $150,000 went to direct mail, while the PAC spent $40,000 on giving to candidates and causes.

The 2008 vice presidential nominee, former Alaska Gov. Sarah Palin, pulled in $2.13 million last year, but spent only about $1.2 million. Her primary outreach expenditures were Internet-based -- fitting for the prominent Facebooker -- and the PAC spent about $57,000 on candidates and causes.

But those three are already established national candidates.

Extensive direct mail spending is a way to begin building a national presence, said Scott Reed, a Washington political consultant who ran Bob Dole's 1996 presidential campaign.

"The ability to prospect and build a direct mail file of contributors and supporters is invaluable," said Mr. Reed, who has not advised any of the potential 2012 candidates.

"That not only allows you to perform with your PAC, but it allows you to go back and raise more money from these folks as you move to the next level. A smart PAC spends a lot of time renting lists and testing mail and themes to raise not only money, but to gain support. And often if you break even you're ahead of the game ... because you picked up an asset that you can now carry on to the future. They've made a commitment to you by signing a check. They're usually not going anywhere."

Overall in 2009, America's Foundation, which is run by a few part-time staff members, raised about $1.25 million and spent about $1.26 million.

But Michael J. Malbin, a professor and director of the Washington-based Campaign Finance Institute, said direct mail fundraising is too 20th century.

"It's a one-way pipeline, as opposed to a more interactive [tool]," he said.

"It seems to me that relying on direct mail at the outset of an insurgent campaign or an upstart campaign seems old-fashioned, but it may be, you don't always have the choice of the tool you can use. You may not have the people to tap into through Netroots."

Mr. Santorum, 51, has used direct mail since he began the PAC while serving in the House of Representatives in the 1990s. After ramping up that spending in 2009, Mr. Santorum in this key election year will be more oriented toward contributing to conservative candidates and traveling the country in support of them, Ms. Davis said.

He's made or planned trips to Iowa, New Hampshire and South Carolina this year to speak to Republican groups or stump for candidates -- all key early presidential primary states.

But Ms. Davis said the PAC has sponsored or will fund trips by Mr. Santorum to Kansas, Nebraska, New York, Louisiana, Florida and Michigan, as well.

Time on the campaign trail helps Mr. Santorum in his future aspirations much more than donations to candidates.

"The PAC can give a max of $5,000," Mr. Malbin said. "That doesn't build up much political debt to the other person. The goal is to go out to an event. One thing that people often do is to go out and do an event and then the candidate raises a significant amount of money -- and then the candidate is in significant debt to you."

It's all a part of keeping his name in the national conversation. Mr. Santorum rose to a leadership role in the GOP during his two terms in the Senate but lost by 18 points to Bob Casey Jr. in 2006 -- the biggest losing margin for a sitting senator since 1980.

Since then, aside from piloting the PAC, he has done think tank work and signed a contract to appear regularly on Fox News programs. He also writes a weekly column for The Philadelphia Inquirer.

His appeal beyond Pennsylvania is clear in the geography of his donor base: In the second half of 2009, only 8.4 percent of his PAC donations came from the state he once represented in Congress.

"Rick has the ability to build a right-of-center social conservative coalition that can be very influential in the next presidential election," Mr. Reed said.

And the PAC is central to that mission.

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