Ohio Governor John Kasich has dropped out of the presidential race after struggling to gain traction against Republican front-runner, Donald Trump.
Mr. Kasich did not have a path to secure the nomination outright, but pledged to lobby for his candidacy during the Republican convention in July, the BBC reports.
Mr. Trump holds a commanding lead and is closing in on the nomination.
His likely opponent will be Democratic front-runner, Hillary Clinton, who lost the Indiana primary to Bernie Sanders.
It was a surprise win for the Vermont senator who continues to attract huge crowds to his rallies, but his opponent has an almost insurmountable lead.
Speaking to CNN about taking on Mr. Trump, Mrs. Clinton said he was a “loose cannon” who had ran a “negative, bullying” campaign.
The New York businessman has made several controversial remarks ever since he launched his White House bid by labelling Mexicans as rapists and criminals.
Several senior Republicans said on Wednesday they will not back him, with some saying they would prefer to vote for Mrs. Clinton.
Mr. Kasich’s announcement, which will be made later but has been leaked to the United States media, clears Mr. Trump’s path although he was never a significant threat and only won his home state.