Lack of money caused Rick Santorum's exit from the GOP race Rick Santorum said Thursday that he ended his presidential bid because he ran out of money, his campaign was in debt and he would have been unable to air any advertising in Pennsylvania. "Money isn't everything in politics, but you do have to have enough to be successful and we were reaching a point where we were frankly not in the position," Santorum said in his first interview since suspending his campaign Tuesday, on the "Today's Issues" show on the American Family Radio Network. We simply didn't have the resources to compete going forward. The remarks were the most direct Santorum has made about why he dropped out of the race two weeks before a critical primary in his home state of Pennsylvania. Previously, he alluded to his seriously ill youngest child who was recently hospitalized, as well as the allocation of delegates in upcoming contests. In the interview with Family Research Council President Tony Perkins, Santorum said his campaign organization had grown and had been "just burning through cash" in recent contests, while donations slowed to a "trickle," leaving the campaign in debt for the first time and for an amount that Santorum said he was not comfortable with. "I'll be honest with you, Tony, in the last week after Wisconsin, we basically raised almost no money," Santorum said. We had solicitations going out and people were just emailing back saying the race was over. The April 24 primary in Pennsylvania, which Santorum represented for 16 years in the Senate and the House, was considered a must-win for him, and a loss would have been embarrassing as well as damaging to the credentials he established during the campaign. Polls showed Santorum's one-time large lead in Pennsylvania over national front-runner Mitt Romney slipping away, and Romney bought millions of dollars in television advertising. "We were looking at probably not being able to spend a penny on advertising," Santorum said. You reach a point where you want to compete, but you have to be able to compete, and we felt we couldn't. Santorum did not discuss whether he would endorse Romney, the presumptive GOP nominee, but he congratulated him for his win in Wisconsin, which effectively ended the race, as well as his campaign's ability to "spin" the media. He warned that the tactics Romney used to win the primary may not be successful in the general election against President Obama. As for Santorum's future, he pledged to remain a voice for the conservative voters who drove his insurgent campaign, and he said he would work on electing fellow-minded conservatives to Congress and state legislatures. "Let me assure you, we are not going to go quietly," he said.