Washington: Republican presidential front-runner Donald Trump's concerns about how delegates are allotted turned into a roar on Monday as he accused the campaign of rival Ted Cruz of buying votes after his weekend win in Colorado.
The New York billionaire amassed a delegate lead by winning many state contests but Cruz has proven tenacious in pursuit of every last delegate available by other means in hopes of winning the nomination at a brokered Republican convention in July.
Cruz's campaign has worked effectively in states where the delegate allocation process is more complex, such as Colorado, where the US senator from Texas picked up 34 delegates on Saturday at the state Republican convention.
"The people out there are going crazy, in the Denver area and Colorado itself," Trump said on Fox News. "They're going absolutely crazy because they weren't given a vote. This was given by politicians - it's a crooked deal."
Trump's camp has amplified complaints about the delegate allocation system, which varies from state to state, as the prospect of a contested Republican convention looks more likely to determine the party's nominee for the November 8 election.
A Republican candidate needs 1,237 delegates to clinch the nomination and avoid a convention floor fight, which could involve several rounds of voting for delegates.
Trump on Monday also accused Cruz of trying to steal delegates in South Carolina, which Trump won. Cruz came in third in that state in February but won three delegates Saturday at congressional district meetings, according to local media.
"Now they're trying to pick off those delegates one by one," Trump said on Fox News. "That's not the way democracy is supposed to work. They offer them trips, they offer them all sorts of things and you're allowed to do that. You can buy all these votes.
"What kind of a system is that?... It's a rigged system."
Trump's new adviser on delegate matters, Paul Manafort, said on Sunday the campaign would protest what he called Cruz's "Gestapo tactics, the scorched-earth tactics" on delegates.
A tweet from the Colorado Republican Party appeared to briefly verify Trump's fears that state party officials favored Cruz. After Saturday's results, the party tweeted, "We did it. #Never Trump," the Denver Post reported.
The party then deleted the tweet, which it said was unauthorized, and said it was investigating.
Colorado Republicans defended their voting process on Twitter Monday morning, re-tweeting a post by commentator Ari Armstrong who called the system "representative".
"Claiming delegates were 'stolen' insults the Republicans who participated," Armstrong wrote, which the state party re-posted.