Indiana
His reasoning: "I’ve played his golf course, I’ve stayed in his hotel."
The state’s demographics favor Ted Cruz, but the economics and polls point to a Donald Trump win.
Republican evangelicals were made wary when the front-runner revealed a more liberal side to his social views.
He sidestepped the question a total of nine times in one interview.
WHAT'S HAPPENING
Is this game over for the GOP?
The announcement comes ahead of Tuesday's primary in the state.
Fiorina, who also sought the nomination earlier this cycle, has been a vocal supporter of Cruz on the campaign trail.
Indiana's primary is next "and Hoosiers will see Donald Trump for the fraud he is,” an anti-Trump adviser said.
Women are calling the governor to protest tighter restrictions to abortion access in Indiana.