In order to win the Republican nomination, a candidate needs to have 1,237 delegates. Trump reached 1,238 delegates on Thursday, May 26.
According to the AP, Oklahoma GOP chairwoman Pam Pollard is one of the delegates to support the former Celebrity Apprentice host in his run for the White House.
"I think he has touched a part of our electorate that doesn’t like where our country is," Pollard said in a statement. "I have no problem supporting Mr. Trump."
Trump, 69, has been the Republican presidential front-runner for months, and the presumptive nominee for several weeks, while former Secretary of State Hillary Clinton and Senator Bernie Sanders continue to go head-to-head for the Democratic party spot.
Up next, Trump is eyeing a debate with Sanders, 74, ahead of the California primary in June. On Wednesday, Trump said on Jimmy Kimmel Live! that a debate with Sanders "would have such high ratings."
Sanders responded via Twitter: "Game on. I look forward to debating Donald Trump in California before the June 7 primary."
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