NBC News reports that this is shaping up to be a significant week in the race for the GOP presidential nomination. If Mitt Romney wins tomorrow’s Michigan primary, he will remain on track to becoming his party’s nominee. It still won’t be easy, he still will have a challenge in next week’s Super Tuesday contests, but a win in Michigan means he’ll probably be President Obama’s general-election opponent in November. (How formidable he’ll be against Obama is an entirely different question.) Yet a loss in Michigan would be DEVASTATING to his candidacy, given all of his advantages in the state and given all the mistakes Rick Santorum has made in the last several days. More importantly, a loss in Michigan would send the GOP establishment into a panic, would lay the groundwork for another candidacy, and would introduce chaos in the Republican race beyond anything we’ve seen yet. Bottom line: A lot is riding on tomorrow’s outcome in Michigan. And for what it’s worth, it does appear Romney is on the right track.