Rick Wilking / Reuters

Few Americans know what it’s like to stand onstage for a nationally televised presidential debate. And the few who do have strong partisan biases. With both of those things in mind, I listened Monday as Chris Christie, the former New Jersey governor and a Republican candidate in 2016, discussed the upcoming Democratic debates during an interview with the Atlantic editor Jeffrey Goldberg at the Aspen Ideas Festival.

When the large Democratic field gathers tonight and Thursday for televised debates, many candidates will be appearing on the national stage for the first time.

Under those lights, “there’s only two options,” Christie said. “You either shine or you melt. That’s it.” His gut tells him that Mayor Pete Buttigieg will melt and that Senator Cory Booker may shine. But in his estimation, it’s hard to tell who is likely to do what, and whatever happens is likely to significantly affect the race going forward.

Hence the high drama of the moment.

“[Governor] Scott Walker at one time was, like, the front-runner in Iowa,” he recalled. “He literally sweated himself out of the campaign at the Reagan Library debate. Couldn’t answer, was sweating profusely, wasn’t ready. This was a guy who’s faced up to unions in Wisconsin and put up with a lot of very difficult issues … No one could have predicted that Scott wouldn’t perform.”

Former Vice President Joe Biden is leading in polls. In Christie’s estimation, he is also the Democratic candidate best positioned today to convince “those 77,000 voters in Michigan, Wisconsin, and Pennsylvania who won the election for the president.”

Yet Christie’s advice for rival candidates whom he regards as viable (Senators Elizabeth Warren, Kamala Harris, Amy Klobuchar, Bernie Sanders, and Booker) is to refrain from attacks for now. “Don’t go after old Uncle Joe too fast,” he said, “because Uncle Joe may kill himself right now. We’ve watched two Joe Biden presidential campaigns before. And they were not sterling examples of discipline.”

Perhaps Biden will be jittery, expecting attacks; the much lesser-known Democrats are likely to feel pressure to force a memorable moment, Christie said, for fear they won’t otherwise appear in the second debate. Biden may well respond by putting his foot in his mouth. If not, there’s plenty of time to attack him later.

And if Biden does put his foot in his mouth, Christie speculated, he won’t be able to survive it in the way Donald Trump repeatedly did during his 2016 campaign.

“He’s not Trump, where Trump could do almost anything and it didn’t matter,” Christie said. “See, Trump got the break because people said, ‘Hey, can’t blame him for that. He’s not a politician … He’s going to stir things up.’” Whereas with Biden, “they’re going to go, ‘You’ve been in politics since you were 29 years old. You’re now 77. You know you’re not supposed to say stuff like that. You’re out.’”

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