Kasich, the Ohio governor, had stayed in the race in hopes of persuading Republicans to choose him as the nominee at a contested convention in July. He ended his campaign as a clear path emerged for Trump to amass the delegates needed to secure the nomination outright.
"As I suspend my campaign today, I have renewed faith, deeper faith that the Lord will show me the way forward and fulfill the purpose of my life," Kasich said in Columbus, the Ohio state capital.
Some U.S. Republican lawmakers said they would support Trump since he will be the nominee, stressing the importance of defeating Democrat Hillary Clinton in the general election. One of those was 2008 presidential nominee John McCain, a U.S. senator from Arizona who is seeking re-election this year and was insulted by Trump last year.
"As John McCain has said, he will support the nominee of the Republican Party, who is now presumptively Donald Trump," said McCain`s Senate campaign spokeswoman, Lorna Romero.
But the wounds from a brutal primary battle were still raw among many Republican loyalists who simply cannot bear to support Trump because they worry he could spell disaster for the party in November.
Republican Senator Ben Sasse of Nebraska reiterated statements that he would not back Trump and pointed to a February Facebook post in which he said he would look for an alternative candidate if Trump became the nominee.
Nebraska`s other U.S. senator, Republican Deb Fischer, made clear in an interview with Nebraska Radio Network that she would support the party`s nominee but was not comfortable with Trump.
"Mr. Trump is going to have to work hard to bring the party together,” she said. “He’s going to have to work hard to explain his stance on different issues and to talk about the principles and values he holds. I look forward to having a robust race here.”
South Carolina`s Republican governor, Nikki Haley, issued a statement saying she would support the Republican nominee but was "not interested" in being the party`s vice presidential running mate.
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