(CBS News) Saturday is primary day in Louisiana in the Republican presidential race.
It could be a big day for Rick Santorum. Polls put him way up on Mitt Romney in the Bayou State.
But Romney is riding a wave of momentum nationally after his big win in Illinois Tuesday.
A new Gallup poll shows him leading Santorum 40-26, with his highest level yet of national support from Republicans.
And A.B. Stoddard, associate editor of The Hill newspaper, said on "CBS This Morning: Saturday" that, "A victory in Louisiana will be good for Santorum. But it doesn't change the math at all. Mitt Romney still has a two-to-one delegate advantage over Rick Santorum, as he has the week before last, the week before last, the week before last, and he will next week. So, the math is pretty much over at this point for Rick Santorum. Wisconsin would be his last stand, on April 3. He has plummeted in the polls there. He could do OK. I'd doubt that he could win there, and I think it will be over then, on April 3." (To see the interview, done by "CBS This Morning: Saturday" cophost Ben Tracy, click on the video below)
Determined to play the front-runner, Romney kept his focus on President Obama Friday, on the second anniversary of the health care reform law.
"You'll note the White House isn't celebrating 'Obamacare' today," he said on the stump. "They don't have any big ceremony going on. The president's not giving speeches on Obamacare -- and that's for a reason. Most Americans want to get rid of it and were among those Americans. I want to get rid of it, too."
Santorum started Friday with a bang, visiting a target range in Louisiana, a state where he leads Romney in the polls by double digits, and in one new poll by a whopping 16 points, 43-27.
But Santorum spent much of the day on the defensive. "I would never vote for Barack Obama over any other Republican, and to suggest otherwise is preposterous," he told a crowd.
A day earlier, in Texas, he had seemed to suggest he would prefer Mr. Obama over a candidate like Romney when Santorum said, "If you're going to be a little bit different, we might as well stay with what we have instead of taking a risk with what may be the 'Etch-a-Sketch' candidate of the future." Santorum was referring to a gaffe by a top Romney adviser, who said the Romney campaign could be like an Etch-a-Sketch in the fall, completely re-setting. The remark conjured up charges by Romney rivals that Romney is a flip-flopper.
Santorum spent much of Friday explaining what he had meant with his remark about Romney and the president.
"I'll vote for whoever the Republican nominee is," Santorum stressed. "I mean, I'll work for them. Barack Obama is a disaster, but we can't have someone who agrees with him on some of the biggest issues of the day," a reference to Romney.
To see Chip Reid's report, click on the video in the player above.