With a #NeverTrump hashtag and a growing list of high-profile people and groups declaring that they will never support Donald Trump as the nominee of the Republican Party, the effort to block Trump from winning the nomination is gaining force. But former House Speaker Newt Gingrich on Tuesday previewed what he said will be the single most effective argument for strong-arming anti-Trump Republicans back into the fold if he is the nominee.

“You are either going to elect Hillary Clinton who will, I think, be the most corrupt president in American history, or you’re going to help elect Donald Trump,” Gingrich told Fox News Tuesday morning. “There’s no middle ground. You can’t say virtuously, ‘Oh, I’m going to be neutral.’ If you’re neutral, you’re helping elect Hillary Clinton.”

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Running through a list of Republican objections to Clinton -- including foreign policy, Supreme Court picks, her use of a private email server for sensitive State Department communications, and alleged corruption within the Clinton Foundation -- Gingrich said, “It’s a moral case. A citizen who does not actively support the Republican candidate is, in effect, helping to elect Hillary Clinton. I don’t think very many of these folks in the end are going to help elect Hillary Clinton.”

And while he declined to endorse Trump, saying that he would support whomever the party nominates, Gingrich was not sparing with praise, either, predicting a huge Trump landslide in today’s Super Tuesday primaries.

“Trump will tower over all of them,” he said. “The scale of his victories from Massachusetts and Vermont, all the way across to Alaska, is going to be pretty stunning.”

He continued, “That poses, for the Republican establishment, a very big challenge. For the next few weeks, there’s going to be a frenzy to try to stop him. I don’t think the frenzy will work, and if it doesn’t, then both Trump and the Republican leadership, the traditional leadership, face a big decision.

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“Do they want to turn this into a Goldwater campaign like 1964 and have the party get beaten badly, or do they want to turn into a Reagan campaign like 1980 and have the party win a stunning victory? There’s no middle ground here.”

Gingrich defended Trump against claims that he is not a real conservative – a key talking point for other candidates, including Texas Sen. Ted Cruz and Florida Sen. Marco Rubio.

Cruz, on Monday, described Trump as “a New York City liberal who has supported liberal policies, who agrees with Hillary Clinton on issue after issue after issue.”

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While Trump is “not a traditional conservative,” Gingrich conceded, he is “an anti-left, anti-political correctness, anti-stupidity American nationalist, and he applies those four basic principles to try and figure out where he’s going and what he’s going to do. Sometimes that makes him complicated for conservatives because they have these cookie cutters – you are for this, you’re not for that.”

He said, “I think I have pretty good credentials as a conservative, but I also think we’re at a historic moment when 70 percent of the voters in the last national poll favored Donald Trump, Ted Cruz, and Dr. Ben Carson. Seventy percent. Now that says that the Republican Party base is saying to its so-called leadership, ‘you’re not leading the way we want you to.’ And by better than two-to-one, they’re picking outsiders over insiders.”

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