John Kasich is ending his presidential bid, a day after the only other GOP candidate opposing Donald Trump, Ted Cruz, dropped out of the race after Trump's resounding victory in Indiana, CBS News chief White House correspondent Major Garrett confirmed.
The Ohio governor is expected to deliver a statement at 4 p.m. Central Time in Columbus, Ohio.
Kasich had cancelled a press event in Virginia Wednesday, fueling speculation about an exit from the race. He finished third in Indiana, behind Cruz. On Tuesday, Trump won at least 51 of the state's 57 delegates.
Republican National Committee Chairman Reince Priebus referred to Trump as the "presumptive nominee" in a tweet Tuesday night, calling for other Republicans to rally behind the billionaire.
Kasich senior strategist John Weaver took issue with that assessment, saying in a statement Tuesday night that "there is no presumptive nominee" until a candidate reaches the 1,237 delegates needed to lock down the nomination. Trump, after Indiana, has 1,046 delegates, while Kasich has just 152 delegates.
Previously, Kasich, the last man standing against Trump, had pledged that he would continue his campaign "as long as it remains possible."