Carol Platt Liebau
Every sign points to a Romney win tonight, but the real story will lie in his margin of victory.  If he barely ekes one out,his challengers will have a renewed rationale for pushing on with vigor.

But if Romney wins in a romp, exceeding the combined percentages of the second and third place finishers or coming close, he moves forward with even greater strength -- and his challengers lose the argument that a single non-Romney challenger could meaningfully change the dynamic of the race.

It will also be interesting to see how much the quasi-endorsement of Gingrich by Sarah Palin and the endorsement of Herman Cain ends up mattering.  One could argue that Governor Palin has a fair amount riding on Newt Gingrich's performance tonight.

Carol Platt Liebau

Carol Platt Liebau is an attorney, political commentator and guest radio talk show host based near New York. Learn more about her new book, "Prude: How the Sex-Obsessed Culture Hurts Young Women (and America, Too!)" here.