Story highlights Donald Trump currently leads GOP delegate race

Kasich, Cruz alliance may not be enough to deny Trump the nomination

(CNN) The eleventh-hour bid by Ted Cruz and John Kasich to deny Donald Trump the Republican nomination by dividing upcoming contests is bold -- but likely doomed.

The delegate math overwhelmingly favors Trump, who is the only GOP presidential candidate with a realistic shot at securing the 1,237 delegates he needs to clinch the nomination before the Republican convention in July.

Trump currently leads the race with 846 pledged delegates. And with a favorable slate of primaries on Tuesday, he could finish the week on the cusp of 1,000. With 502 delegates still up for grabs beginning next week in Indiana, Trump would likely be on track to hit 1,237 and clinch the nomination in June.

The Cruz-Kasich alliance is aimed at dulling that trajectory with the Texas senator focusing on Indiana while the Ohio governor aims his resources at Oregon and New Mexico. Even in the event they sweep those three states -- taking 109 delegates off the board -- Trump would still be on pace to finish the primary season fewer than 50 votes shy of the magic number.

Anything less, though, would open the door even wider for Trump, effectively guaranteeing him the GOP nod by the last day of voting on June 7.

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