U.S. Republican presidential candidate Donald Trump speaks during a campaign event at an airplane hanger in Rochester, New York, April 10, 2016 Reuters/Carlo Allegri Donald Trump is continuing his crusade against what he calls a "rigged" Republican primary delegate system, complaining on Twitter that more than "one million people have been precluded from voting" in Colorado.

In a series of tweets Wednesday night, Trump claimed the rules in Colorado were designed to prevent him from winning delegates in the state, which held its conventions last weekend.

"Biggest story in politics is now happening in the great State of Colorado where over one million people have been precluded from voting!" he tweeted.

In subsequent tweets, Trump said: "The rules DID CHANGE in Colorado shortly after I entered the race in June because the pols and their bosses knew I would win with the voters. Big protest march in Colorado on Friday afternoon! Don't let the bosses take your vote!"

While most states hold primaries and caucuses that allow average voters to weigh in on who they want as their party's nominee, Colorado's system puts more of the power within the hands of party insiders and activists who turned out for the convention events.

The delegate rules for Colorado were announced in August. But Trump has still blasted the system as "rigged" and implied that Cruz's campaign had offered "goodies" to woo Colorado delegates.

Trump told "Fox & Friends" on Thursday that he would have won Colorado if they hadn't "changed the rules."

"They took it away from the voters, because I would have won in Colorado," Trump said.

When asked if he thought the rule change was because of him, Trump said, "I think so, yeah, I think so, because they saw that I do very well in Colorado, so I think so. Look, it's a crooked system, but what are you going to do? In the meantime, I'm winning."

His comments are the latest in a series of complaints about the Republican Party's system for choosing a presidential nominee. Trump called the delegate process a "crooked deal" on Monday after his rival for the nomination, Texas Sen. Ted Cruz, took all 34 delegates in the Colorado Republican conventions.

Trump said on Fox: "I rely on the voters. I don't rely on politicians. I'm self-funding my campaign. People don't like that, because that means they have no control."