Tuesday's primary could mark the turning point in the GOP Race for President. — Today could be a turning point in the Republican race for President. If Mitt Romney wins Illinois decisively, analysts think he'll create a clear path to the nomination.
If he loses - or barely wins - we could be looking at the first big fight at the republican convention in three decades.
Rick Santorum's facing an uphill battle in Illinois. Romney's leading the polls this election day, but not taking the Land of Lincoln for granted.
Mitt Romney on his third day campaigning in Illinois - the land of Reagan and Obama – is up by 9 points in the latest polls.
Santorum's the underdog - ineligible for 10 of today's 54 delegates because he filed paperwork too late.
On Monday, Santorum tried to re-define the key issue in this race. "I don't care what the unemployment rate's going to be. Doesn't matter to me. My campaign doesn't hinge on unemployment rates," said Rick Santorum, (R) Presidential Candidate.
"I DO care about the unemployment rate. It does bother me. I want to get people back to work," said Mitt Romney/ (R) Presidential Candidate.
Then Santorum clarified. "Of course I care about the unemployment rate. I want the unemployment rate to go down. But I'm saying my candidacy doesn't hinge on whether the unemployment rate goes up and down," said Rick Santorum, (R) Presidential Candidate.
But it's today's numbers - the Illinois vote -that Romney’s team hopes will solidify him as the frontrunner.
Analysts say he needs a win - a big one "A loss in Illinois or even a narrow win by Romney will certainly seed a lot of doubts about the strength of his candidacy,” said NBC News Senior Political Editor Mark Murray.
Tracie Potts, NBC News, Washington.