DENVER (CBS4) – Presidential candidate Donald Trump took his frustration to Twitter Sunday evening over Colorado’s voting process.

Candidate Ted Cruz was in Colorado Springs on Saturday for the state’s Republican Assembly. He took all 13 delegates up for grabs to complete a clean sweep of Colorado.

Trump can still clinch the nomination before the convention, but needs to win nearly 60% of the remaining delegates. New York is a winner-takes-all state, with 95 Republican delegates.