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.
The political fallout could also be disappointing for Cruz and Kasich. They risk the appearance of open collusion, which would fuel anger among the Trump supporters who believe the party is plotting against the billionaire businessman.
For months, Trump has railed against the party and the Republican National Committee for what he insists is a conspiracy to deny him the GOP nomination. On Monday, Trump escalated those attacks as he accused his rivals of collusion.
"They colluded and actually I was happy because it shows how weak they are," Trump said at a campaign rally in Warwick, Rhode Island. "It shows how pathetic they are."
"If the Republicans don't lay off this man, I will never vote Republican," said Tim Wiles, a Trump-leaning voter in Buffalo, New York, said before news of the Cruz-Kasich alliance emerged late Sunday.
Meanwhile, Kasich and Cruz on Monday sought to downplay the significance of their unexpected compromise.
"I don't see this as any big deal," Kasich said at a campaign stop at a Philadelphia diner. "Other than the fact that I'm not going to spend resources in Indiana, he's not going to spend them in other places. So what? What's the big deal?"
Pressed to name the candidate his supporters should back in Indiana, the Ohio governor appeared to go off message.
"I've never told them who to vote for," he said. "They ought to vote for me."
On the trail in Indiana, Cruz explained the move as "a decision to allocate our resources." And like Kasich, Cruz rejected the idea his campaign's maneuvering signaled a "Hail Mary."
"There is desperation on the Trump side," the Texas senator said, predicting Trump would "cry" over the arrangement because he's a "sore loser."