Editor’s Note: Sarah Isgur is a CNN political analyst. She has worked on three Republican presidential campaigns and is an adjunct professor at George Washington University’s School of Media and Public Affairs. She is a graduate of Harvard Law School. The views expressed here are hers. Read more opinion on CNN.

CNN  — 

I’ve been hearing a new conversation in coffee shops and happy hours around the country. One friend makes their prediction of who will win in November 2020, and the other nods in agreement. But then the voices become hushed as the second person asks, “But do you really think the other side will accept the results?”

Sarah Isgur

We’ve experienced the peaceful transfer of power for 230 years, including the constitutionally messy outcomes in 1876, 1888, 2000 and, well, 2016 for that matter. No tanks rolled through the streets and no shadow governments operated from underground bunkers even when the guy with the most votes didn’t end up in the White House.

So why in 2019 do so many Americans – across party lines – believe that if their candidate loses next year it can only be because the election was rigged?

Here’s one place we can look: For the third time in his presidency, Donald Trump has an 86-point gap between what Republicans and Democrats think about him, according to the latest Gallup approval poll. Ninety-one percent of Republicans approve of his job performance to date, while only 5% of Democrats feel the same.

This ties the highest gap Gallup has ever measured in a single survey. President Obama had an 86-point gap two days before his reelection in 2012. President Bush hit the low 80s twice in the run up to his reelection. Reagan only made it into the 70s – also in the fall of 1984. In all 3 cases, the partisan divide peaked during the days and weeks before a highly contested election.

We are still 14 months away from Election Day. But Americans on both sides appear primed and ready to vote.

Just four years ago, only 32% of voters said they were “extremely interested” in the 2016 election. But this week, that same poll shows 59% are extremely interested this time around. And if you only include self-identified partisans, the number jumps into the 60s.

And with stakes this high, Democratic voters appear to be grappling with their own dilemma: vote for a candidate who best exemplifies their visceral loathing for Donald Trump or vote for the candidate who is most likely to beat him?

Current polling shows the race for the Democratic nomination is tightening between Vice President Joe Biden and Senator Elizabeth Warren. But that doesn’t mean voters are picking between them.

The polls are pretty clear that Democratic and Democratic-leaning independent voters would prefer to vote for Elizabeth Warren. They think she’s won every debate so far. And as the 20,000 people who showed up to her New York City rally this week can attest, she leads Biden in voter enthusiasm by double digits.

But nearly half of Democrats and Democratic-leaning voters believe that Biden is best positioned to beat Trump. Barely 1 in 10 think that of Warren.

If history is any indication, there’s every reason to suspect the partisan divide heading into 2020 will get worse. After all, that 86% gap just means we have 14% more to go.

All of this is a big problem for Elizabeth Warren.

As David Leonhardt noted in the New York Times this week, Warren has struggled to win blue collar workers (you remember: the ones that gave Trump his narrow wins in Wisconsin, Michigan, and Pennsylvania?) in her own state of Massachusetts since 2012. She underperformed even her fellow down ballot Democrats in the last election. Voters on both sides of the aisle in these swing states are tuned in and eager to vote, but Biden out performs her in a head to head with Donald Trump in Wisconsin by 9 points, for instance.

Of course, Joe Biden has his own lurking shadows. Unlike Elizabeth Warren, who has developed her following based on her progressive appeal and solid debate performances, Biden’s standing with the Democratic electorate seems largely driven by fear—fear of losing again to Donald Trump. If she can assuage that fear—or if another candidate can prove more viable—Joe Biden could be looking at a swift and total collapse.

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    We’ve got a long way to go in this race, but the growing partisan divide around Donald Trump and the fear of losing to him in 2020 means electability will only grow in importance to Democratic primary voters. And that’s bad news right now for every candidate whose name doesn’t rhyme with Schmiden.

    Note: An earlier version of this article incorrectly said the 2020 election is 16 months away.