Former Republican presidential candidate Jeb Bush has endorsed Texas Senator Ted Cruz for president, calling him a "principled conservative".
Mr Bush, former governor of Florida, dropped out of the race last month after poor showings in state contests.
He said Mr Cruz has shown the ability to appeal to voters and win primary contests, like in Utah on Tuesday.
Republicans must "overcome the divisiveness and vulgarity" Donald Trump has introduced, he said.
If not, the party will certainly lose the White House to Democratic front-runner Hillary Clinton, Mr Bush wrote in a Facebook post.
"Republicans can win back the White House and put our nation on a path to security and prosperity if we support a nominee who can unite our party and articulate how conservative policies will help people rise up and reach their full potential," he wrote, and linked to Mr Cruz's website.
I think Jeb Bush would make a much better president than Ted Cruz, but if he thinks he is the best of what's left standing, then I shall give him my support. This blog now endorses Ted Cruz.