In the Michigan Republican primary Tuesday, Mitt Romney had a near-death experience, but he squeaked out a narrow victory over Rick Santorum. That, says veteran Republican strategist Ed Rogers, has calmed some of the anxiety in Republican circles about Romney's strength as a general election candidate.

"Mitt Romney did what he needed to do to give more certainty and more clarity to the race. He dodged a bullet; it was an ugly win," Rogers says. "It's not over. Santorum is still very competitive."

Romney is still a fragile front-runner, but a win is a win, says Republican consultant Whit Ayres.

"Whenever Mitt Romney's back is to the wall and he absolutely has to win, he's come through so far — first in Florida, now in Michigan. So [the primary]'s results will tamp down the call for a new candidate at least for a week," Ayres says.

Ayres points out that there hasn't been any momentum in this Republican race. Candidates win one round and then go on to lose the next. Plus, the delegate process has turned the GOP primary into a longer-than-expected campaign.