'Greatest test they’ve ever faced': Ex-GOP rep issues challenge to anti-Trump Republicans

A former Republican member of Congress who left the party in protest of former President Donald Trump's grip on the GOP is calling on anti-Trump Republicans to take their opposition to Trump seriously all the way through November.

During a Tuesday segment on MSNBC's Deadline White House, former Rep. David Jolly (R-Florida) told host Nicolle Wallace that while he appreciates former UN ambassador Nikki Haley's numerous criticisms of Trump on the campaign trail, none of it will matter if she still ends up endorsing him in the event he wins the GOP presidential nomination.

"You have built your campaign around questioning Trump's fitness for office, around his competency, around his patriotism, his loyalty to the country," Jolly said to Haley and her supporters. "You've called hi/m unhinged, unstable, you have said his election conspiracies are those of a 'loser,' you have said that he's sided with [Russian President Vladimir] Putin, you have said he's not competent or young enough to be president."

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"Donald Trump beating Nikki Haley does not make Donald Trump more fit for office," he continued. "What changes the dynamic? It actually relies on leadership voices like Nikki Haley's and Chris Christie's, and Liz Cheney and Adam Kinzinger to say, 'we are voting for Joe Biden in November.' And if they fail to do that, they fail the greatest test they've ever faced, probably."

"The voters, many of the voters, are already ready to answer that question, that they'll vote for Joe Biden," he added.

Jolly made his comments as millions voters head to the polls on Super Tuesday in 15 states and territories. Today marks the single busiest day on the primary calendar for both Democrats and Republicans in their respective nominating contests, with a vast bulk of delegates on the line. Should Trump sweep today's contests, he would accumulate almost enough delegates to become the presumptive Republican presidential nominee well in advance of this summer's Republican National Convention, where delegates will officially cast their votes for Trump or Haley.

While Biden doesn't face any serious opposition from Democrats like Dean Phillips and Marianne Williamson (who recently un-suspended her presidential campaign), Haley has notched one win so far in the GOP primary with her victory in Washington, DC last weekend. That win garnered her 19 delegates in the winner-take-all contest.

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Haley has suggested she may stay in the race even if she strikes out on Super Tuesday, but she has not yet publicly indicated whether she would back Trump or vote for Biden in the general election if she's not the nominee. Former New Jersey Governor Chris Christie — who was Trump's most vocal critic while he was still running for the GOP nomination — also hasn't committed to voting for Biden, but did say earlier this year that he would not be casting a ballot for Trump "under any circumstances."

Likewise, former Rep. Liz Cheney (R-Wyoming) has also said she would "never" vote for Trump, but waffled when The View co-hosts asked if she would publicly endorse Biden. The only Republican to do as Jolly has suggested is former Rep. Adam Kinzinger (R-Illinois) — an early backer of Christie — who said he would vote for Biden "in a heartbeat" if the general election were between him and Trump.

Watch Jolly's segment below, or by clicking this link.

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