Washington, April 13

US Republican presidential candidate Ted Cruz is close to ensuring that Donald Trump cannot win the GOP nomination on a second ballot at the party\'s July convention in Cleveland, scooping up scores of delegates who have pledged to vote for him instead of the front-runner if given the chance.

The push by Cruz means that it is more essential than ever for Trump to clinch the nomination by winning a majority of delegates to avoid a contested and drawn-out convention fight, which Trump seems almost certain to lose, The Washington Post reported.

The GOP race now rests on two cliffhangers: Can Trump lock up the nomination before Cleveland? And if not, can Cruz cobble together enough delegates to win a second convention vote if Trump fails in the first?

Trump\'s path to amassing the 1,237 delegates he needs to win outright has only gotten narrower after losing to Cruz in Wisconsin and other recent contests, and would require him to perform better in the remaining states than he has to this point.

In addition, based on the delegate selections made by states and territories, Cruz is poised to pick up at least 130 more votes on a second ballot, according to a Washington Post analysis.

That tally surpasses 170 delegates under less conservative assumptions -- a number that could make it impossible for Trump to emerge victorious.

That is why the race centres on the fevered hunt for delegates across the country. The intensity of the fight has sparked another round of caustic rhetoric -- including allegations from party leaders that Trump supporters are making death threats.

\"It\'s unfortunate politics has reached a new low. These type of threats have no place in politics,\" said Kyle Babcock, a Republican delegate from Indiana\'s third Congressional district.

He received an email from a Trump supporter who warned, \"Think before you take a step down the wrong path.\"

Cruzâ€™s chances rest on exploiting a wrinkle in the GOP rule book: that delegates assigned to vote for Trump at the convention do not actually have to be Trump supporters.

Cruz is particularly focused on getting loyalists elected to delegate positions even in states that the senator from Texas lost.

Cruz said this week that he thinks the odds of a contested convention are \"very high\".

\"In Cleveland, I believe we will have an enormous advantage,\" he told radio talk-show host Glenn Beck.

Trump has a commanding lead in total delegates and the overall vote total, but has complained that Republican leaders are conspiring against him in a bid to silence his supporters.

\"The RNC should be ashamed of itself for allowing this to happen,\" Trump said on Tuesday night while campaigning in Rome, N.Y.

Paul Manafort, a senior adviser to Trump, said he was confident that Cruz will never have a chance to convert Trump delegates.

\"Just because [Cruz] has won some delegates in a state where we have the delegates voting for us is not relevant until and unless there\'s a second ballot,\" Manafort said. \"There\'s not going to be a second ballot.\"

When the presidential nomination vote is held at the convention, 95 percent of the delegates will be bound to the results in their states for the first vote, giving Trump his best shot at securing a majority.

But if Trump falls short, the convention will cast a second ballot in which more than 1,800 delegates from 31 states -- nearly 60 percent of the total -- will be unbound and allowed to vote however they want.

By the third round, 80 percent of the delegates would be free, sparking a potential free-for-all that could continue for several more rounds.

That is the crux of the state-by-state battle that is playing out over the next two months as Republicans gather at the precinct, county, congressional district and statewide level to choose convention delegates.

\"If we go into a contested convention, we\'re gonna have a ton of delegates, Donald is gonna have a ton of delegates, and it\'s gonna be a battle in Cleveland to see who can earn a majority of the delegates that were elected by the people,\" Cruz told a meeting of the Republican Jewish Coalition in Las Vegas on Saturday.

He predicted that the first ballot \"will be the highest vote total Donald Trump receives. And on a subsequent ballot, weâ€™re gonna win the nomination\".

Cruz to block Trump on second ballot at GOP convention