New York billionaire Donald Trump hopes that Indiana's nominating contest on Tuesday will make him unstoppable in what originally had seemed to many a quixotic quest for the Republican presidential nomination. The famously blunt-spoken real estate mogul holds a double-digit polling lead over U.S. Senator Ted Cruz of Texas, who has been campaigning in the Midwestern state almost non-stop since mid-April. Cruz has trumpeted Indiana, one of the last big states left in the fight to get onto the November ballot, as his golden moment to force a brokered nomination at the party's July convention. But it appears to be shaping up as his Waterloo. Fresh off a sweep of five Northeast states last week, Trump hopes a win in Indiana will put him within reach of the 1,237 delegates required to lock up the Republican presidential nomination before the convention.

Donald Trump Kamil Krzaczynski | Reuters

Cruz has been Trump's strongest rival but still trails him considerably in the delegate race. He has been struggling to keep Trump from reaching the 1,237 threshold and force a brokered contest, which, after a string of big losses in April, is Cruz's only chance of securing a spot on the Nov. 8 ballot.

A loss in Indiana would be particularly crushing for Cruz, who has argued that his brand of religious conservatism is a natural draw for heartland Republicans. He won the endorsement of Indiana's conservative Governor Mike Pence. In addition, Cruz was looking for smoother sailing in Indiana after he and Ohio Governor John Kasich, a distant third in the Republican nominating contest, reached a "stop-Trump" deal in which Kasich would steer clear of Indiana while Cruz would do likewise in Oregon and New Mexico. But the waters are looking choppier for Cruz, with the senator losing considerable ground against Trump in opinion polls as voting has neared.

Cruz last week also announced his choice for a prospective vice president, the former presidential contender and Hewlett Packard chief executive Carly Fiorina, during an event in Indiana that some criticized as premature. "I trust the people of Indiana to differentiate," Cruz said on Monday at a campaign stop. "We are not a bitter, angry, petty, bigoted people. ... I reject that vision of America," he added in a swipe at Trump. Trump now has 996 delegates, compared with 565 for Cruz and 153 for Kasich. Another 57 delegates are up for grabs in Indiana, a state that has voted Republican in nine of the last 10 presidential elections. New blood

Trump has drawn both passionate support and vitriolic condemnation with his hardline stands on immigration and national security — including a call to build a 1,000-mile wall along the Mexican border that he says Mexico would pay for and a bid to temporarily banning Muslims from entering the country.

Julie Blackwell Chase, a clerk treasurer of Bedford in southern Indiana, said she voted early for Trump in part because she appreciated his willingness to break with conventional politics. "We need new blood," she said. But the outcome in Indiana may also ride on the votes of evangelicals, after Trump offered praise for Planned Parenthood family clinics and signaled support for gay and transgender rights, views that rankled some Christian conservatives. Clark County Sheriff Jamey Noel, chair of the county's Republican party, said he is voting for Cruz. "Traditional Republicans and Republicans who understand how we elect our president, or pretty much everyone who's conservative, likes Cruz," he said.