Why this day changes everything for GOP

Updated 12:19 PM EDT, Tue March 15, 2016
SHELBURNE, MA - MARCH 01: Voters check in before casting their ballots in the Shelburne Town Hall on March 01, 2016 in Shelburne, Massachusetts. Officials are expecting a record turnout of voters in Massachusetts, one of a dozen states holding Super Tuesday presidential primaries or caucuses. (Photo by Matthew Cavanaugh/Getty Images)
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SHELBURNE, MA - MARCH 01: Voters check in before casting their ballots in the Shelburne Town Hall on March 01, 2016 in Shelburne, Massachusetts. Officials are expecting a record turnout of voters in Massachusetts, one of a dozen states holding Super Tuesday presidential primaries or caucuses. (Photo by Matthew Cavanaugh/Getty Images)
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Story highlights

Buck Sexton: Donald Trump may win Ohio and Florida, clearing path to GOP nomination

For anti-Trump forces, Tuesday is single most important day of election, Sexton says

He says only two options left for them: an anti-Trump war of attrition or a Cruz miracle

Editor’s Note: Buck Sexton is a political commentator for CNN and host of “The Buck Sexton Show” on TheBlaze. He was previously a CIA counterterrorism analyst. The opinions expressed in this commentary are his.

(CNN) —  

The moment that many Republicans thought – even hoped – was impossible is now upon us: By Tuesday’s end, Donald Trump could become the de facto presidential nominee of their party. Whether he does will largely come down to the will of voters in two states: Ohio and Florida.

Based on the most recent polls, a Trump victory appears to be a tossup in Ohio but a shoo-in for Florida, where he leads by high double digits. Every realistic scenario shows Trump building on his lead Tuesday, and perhaps extending it beyond the reach of his opponents entirely. The GOP’s day of reckoning has come.

Your guide to Super Tuesday 3

It’s not just delegate math but campaign momentum that hangs in the balance. If Trump finishes first in the winner-take-all states of Ohio and Florida, he will be more than halfway to the 1,237 delegates he needs to lock up the GOP nomination. Just as importantly, he will have prevailed in two of the most essential swing states for the upcoming general election.

The narrative of Trump as the only legitimate nominee and best contender to beat Hillary Clinton (or Bernie Sanders) will become gospel among his supporters and increasingly difficult for his opponents to counter.

Even the rosiest scenarios for the anti-Trump forces now look pretty bleak over the long run. If Trump wins Florida but loses Ohio, he will maintain a substantial delegate lead with the likelihood of strong primary finishes in delegate-rich states such as New York, California and New Jersey ahead. And if he fails to win either Ohio or Florida, which is highly unlikely, he will still get enough delegates in other contests to remain in first place and face a fractured field of candidates going forward – as Marco Rubio and John Kasich will be almost certain to stay in it if they have big hometown wins.

Turning to Ohio, Trump cuts into Kasich

This is the painful reality for the GOP establishment: No matter what the outcome of Tuesday’s winner-take-all primaries, it already has no good options to stop The Donald. Every other candidate’s pathway to victory looks long and ugly. And even if Kasich manages to hold his home turf in Ohio, Rubio pulls out a miracle in Florida and Sen. Ted Cruz has strong finishes in Missouri, Illinois and North Carolina, the strategies to stop Trump are long shots at best.

Donald Trump has almost won the nomination. Now he has to win the GOP.

For those conservatives, libertarians and mainstream Republicans who refuse to give in and want to beat Trump, there are really only two options left, and neither will be easy: