Joe Biden is setting a bear trap for himself by insisting that Democrats should back him solely on the “electability” issue.

He even had his wife, Jill, as a campaign surrogate, admit to the party’s far-left base that their preferred candidates “might be better on, I don’t know, health care than Joe is” at a New Hampshire campaign event broadcast by MSNBC.

Mrs. Biden, however, married that admission to a warning: “You’ve got to look at who’s going to win this election, and maybe you have to swallow a little bit and say, ‘Okay, I personally like so and so better,’ but your bottom line has to be that we have to beat Trump.”

Let’s play that again: “swallow a little bit.” Maybe this strategy will work, but Biden is just as likely to get his electoral hind legs maimed for the effort.

Trying to sell yourself on the basis of electability has a long pedigree. Of failure.

Lamar Alexander ran in the Republican presidential primaries in 1996 on the slogan of “ABC: Alexander Beats Clinton.” He finished third place in the Iowa caucuses and dropped out before the “Super Tuesday” primaries.

Alexander tried again in four years. That time, he didn’t even make it to the Iowa caucuses.

The 1996 election may seem like ancient history to folks, but how about 2016? Is that recent enough?

Both Jeb Bush and John Kasich were supposed to be more “electable” than Donald Trump and were explicitly sold on that basis. Both had experience governing large states. Both could “credibly” challenge Hillary Clinton. And both went over like a led balloon with primary voters.

We can quibble with the judgment of those voters, but who exactly went on to be “electable” by defeating Hillary Clinton? Why, Donald J. Trump.

If you are going to make the case for electability based on polls, you’re dancing on quicksand. Electability changes from poll to poll. The Biden campaign experienced a glimpse into its very likely future this week. Monmouth University released a poll showing Biden had dropped 13 points and was running third behind Bernie Sanders and Liz Warren. Fortunately for Biden, Monmouth later renounced its own poll and labeled it an “outlier.” But these events underscore the defect in Biden’s strategy: He’s one bad poll away from having to retool his campaign.

Perhaps the Biden campaign believes the other Democratic candidates are so fatally flawed voters will inevitably see the light and choose the former vice president. This thought isn’t outlandish (it’s a pretty wacky bunch running for president). The problem is that Biden himself is fatally flawed. He commits a gaffe at every single campaign event. Literally. Just this week Biden thought he was in Vermont when he was actually in Keene, New Hampshire. And then he deviated from his prepared remarks babbling about what the world would be like if Barack Obama had been assassinated in 2008.

What the Biden campaign is betting is that they can bluff their way into the nomination.

But what if primary voters are of a mind to call that bluff and go for another candidate who more clearly reflects their far-left values?

A write-up for the progressive website Common Dreams admitted that “the former vice president has a commanding lead in national polls and in three early primary states Iowa, South Carolina, and Nevada.”

But! “Sen. Bernie Sanders (I-Vt.) leads Biden in New Hampshire [and] the first contest, in Iowa, is still months away.”

Common Dreams’ bottom line was that “with a field of 23 candidates, Biden’s lead is far from a sure thing,” and many activists and interested parties have been less measured in their assessments.

“Jill Biden may have settled for her husband,” wrote New York magazine staff writer Sarah Jones, “but I’m not sure why anyone else should.”

Here’s an important question that strategists on the Biden campaign should be answering right at this moment: If the “electability” of your candidate goes away, what’s plan B? Do you even have one?