"He has the intestinal fortitude to change the federal government. The direction of the country needs to be changed," Combs said.

Previously Combs had endorsed Gov. Rick Perry, campaigning with him in Iowa before that state's first-in-the-nation caucuses. Reminded that Perry has endorsed Santorum's rival, former U.S. House Speaker Newt Gingrich, as the conservative the country needs, Combs said, "Respectfully, I have my own view. I'm more impressed by Senator Santorum."

In the 2008 presidential campaign cycle, Combs backed former New York Mayor Rudy Giuiliani, perceived by many to have been the most liberal Republican in the race. She defended that decision to the Tribune today. "What I was looking at was, in case of an enormous international crisis, who could stand up for the U.S.?"

Combs is widely expected to run for lieutenant governor in 2014 against a field of conservative heavyweights, possibly including Agriculture Commissioner Todd Staples, Land Commissioner Jerry Patterson, and state Sen. Dan Patrick, R-Houston. Last year she made headlines by revealing that she now considers herself pro-life after a long political career in which she acknowleged she was pro-choice with exceptions, prompting her prospective challengers to argue that her late-in-life conversion was all about electoral politics. Patterson told the Tribune today that he considered Combs' decision to endorse Santorum to be another effort to shore up her bonafides with conservatives. By contrast, he said he would not endorse in the 2012 race. "I don't need to prove anything," he said.

Combs insists the 2014 contest had nothing to do with her decision. "This is about 2012," she said. "We're in a serious presidential race. It's a fight I want to be engaged in."

The Texas presidential primary won't come off until the end of May -- more than two months from now. Why did Combs decide to endorse Santorum today instead of waiting until the campaign here had begun in earnest? "I think we've got a chance after Super Tuesday to give Senator Santorum a real boost," she said. "Waiting until May could be too late."