Story highlights Jeb Bush has slightly modified his response to whether he'd vote for Trump if he were the GOP nominee

He now says that he doesn't think it's possible for Trump to secure the nomination

The former Florida governor is marred in low single digit poll numbers

Hooksett, New Hampshire (CNN) Like some of his Republican rivals, Jeb Bush has grudgingly pledged in the past to support Donald Trump if he becomes the GOP nominee, underscoring a sentiment of anyone-but-Hillary-Clinton.

Now, more than ever before, Bush and other candidates find themselves in a corner after the Republican front-runner has fueled new levels of bipartisan scorn over his proposed policy of banning Muslims from entering the United States.

The nominee question is one that Bush no longer answers with a reluctant "yes," asserting instead that a future Trump nominee is simply impossible.

"That's a hypothetical I reject out of hand," Bush said to laughs Tuesday night in New Hampshire when a Democratic voter asked him what he would do if Trump becomes the nominee.

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