Mike Carlson / AP

On Wednesday, Ted Cruz announced he was planning a “major announcement”—potentially unveiling his vice-presidential pick—in a last-ditch effort to halt Donald Trump’s march to the nomination. WMUR and National Review’s Tim Alberta report that Cruz will name Carly Fiorina to his ticket, apparently hoping that she can expand his appeal among voters he’s struggled to reach, ahead of fiercely contested primaries in Indiana and her home state of California.

There’s some irony in Cruz’s struggle to hold on for long enough to force a contested convention. In early spring, he alleged it would lead to voters’ “revolt” if the evil Washington establishment colluded to elect its favored candidate. All the talk was just D.C. types in a “fevered frenzy,” he said, upset because “their golden children” have been rejected by voters.

Fast-forward a couple months, and Cruz is now banking on a contested convention as his only avenue to win the nomination.

But while Cruz’s calculus has changed in recent weeks, the obstacles in his path haven’t: He still needs to halt Trump’s gains, particularly after Trump’s string of wins in the Northeast, and Cruz still must contend with delegate math that’s not currently working in his favor. Cruz and his supporters are now looking to Indiana to bolster his delegate count, and to justify his candidacy. Trump, meanwhile, is now calling himself the presumptive nominee. “Tonight, this campaign moves back to favorable terrain,” Cruz said Tuesday, soon adding: “The question is, Can the state of Indiana stop the media’s chosen Republican candidate?”

Winning Indiana’s 57 delegates next Tuesday wouldn’t boost Cruz to Trump’s level, even if it would keep the front-runner’s numbers down. After Trump’s big wins in Connecticut, Delaware, Maryland, Pennsylvania, and Rhode Island on Tuesday, he clocks in at roughly 950 delegates. Cruz and Kasich stand at approximately 560 and 150, respectively, according to the Associated Press’s latest count. Candidates need 1,237 to clinch the nomination ahead of a convention.

The Wall Street Journal reports that Cruz needs Indiana to fall in line behind him as Wisconsin did earlier this month. He won 36 delegates and 48 percent of the vote there. But while the states’ Midwestern profiles might be similar—and Cruz’s team has been on the ground for a while now—he doesn’t have the same following:

Mr. Cruz has none of the structural advantages he enjoyed in Wisconsin, where the GOP governor and conservative talk-radio hosts backed him to block Mr. Trump. Indiana’s most respected Republican voices have stayed neutral, and local conservative media haven’t picked sides ahead of the May 3 vote.

Trump’s operation is also investing heavily in Indiana, for the same reason Cruz’s is: math. “Indiana is the highest priority for us,” campaign manager Corey Lewandowski told WSJ. “We want to ensure that, mathematically, Ted Cruz is eliminated.”

Cruz might not have structural advantages in Indiana, but he does have some outside help. “Never Trump” players like Our Principles PAC and the Club for Growth are investing in TV advertising. And Cruz does ostensibly have a pact with rival John Kasich to help Cruz win the state, though the health of that arrangement looks tenuous.

Whether Cruz wins or loses in Indiana, his prospects beyond that state are uncertain, as a recent McClatchy report detailed:

There’s hardly any assurance Kasich can win Oregon May 17 or New Mexico three weeks later. And Trump remains far ahead in polling in the June 7 states of New Jersey, with 51 delegates, and California, with 172 … In the nine states with primaries after Indiana, Cruz currently is favored only in two states with small delegate hauls, Montana and South Dakota.

For now, Trump sounds ready to fight at the convention. On Tuesday night, he asked how the Republican party could tell voters “we are going to choose a man that lost by 5 million votes and 500 delegates,” referring to one or more of his opponents, “because Trump was 14 delegates short of winning on the first ballot?” Cruz, game for a showdown, must pull out all the stops if he wants to see that happen.

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