GOP presidential hopeful Rick Santorum has been getting help from the anti-abortion group Susan B. Anthony List as he campaigns this primary season, so far receiving nearly $500,000 in ads and other support.

The group has run $249,000 in radio ads in Michigan and Ohio, according to filings with the Federal Election Commission. In addition, a half-dozen members are conducting a tour through the primary states on what they call the "Rick Bus," a bright blue vehicle emblazoned with a giant photo of the candidate.

The group's message is simple, as an ad that aired in Michigan put it: "For people who care about the right to life, Rick Santorum is the only candidate for president."

"The reality is, for Santorum the abortion issue is at his core," the organization's president, Marjorie Dannenfelser, said. "Romney certainly has not been the leader that Santorum has."

The bus tour averages four to five stops per day. Among those traveling are Dannenfelser and Maggie Gallagher, director of the Culture War Victory Fund, a nonprofit group.

The tour began in Michigan leading up to that state's Feb. 28 primary, followed by the Super Tuesday states of Ohio, Tennessee and Georgia and, most recently, Alabama and Mississippi, which vote Tuesday.

So far, the Susan B. Anthony List has not aired any negative ads. But when asked whether the group will spend money against candidates in upcoming races, Dannenfelser said, "We will do what we need to do. We don't have any principle against drawing contrasts between candidates."

In 2008 the group spent $98,001 supporting John McCain and $16,174 opposing Barack Obama. She also says that donations have come "pretty easy" so far from the organization's existing donor base.

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