To hear President Trump and his reelection campaign tell it, he’s a shoo-in for victory in November given how much more enthusiasm he enjoys from his supporters.

“We have more enthusiasm right now with our voters, Brian, than they ever had, than we ever had in 2016,” Trump said last week to “Fox and Friends” host Brian Kilmeade. “And we had greater — nobody ever saw enthusiasm like 2016. They came from the lakes, the rivers. They came from everywhere.”

That “lakes and rivers” thing is a shorthand for Trump’s standard patter about the rush of eager people from unexpected places coming out to vote for him four years ago. And now, he says, people are more enthusiastic even than that!

A Pew Research Center poll released Thursday seems to support at least part of that claim: Trump supporters are, in fact, more enthusiastic about him than are supporters of former vice president Joe Biden, Trump’s likely opponent.

But if you dig into the Pew numbers a little more, you discover something interesting. Yes, Trump supporters are more fervent in their support — but they’re no more likely to say they will certainly stick with Trump.

What gives? How could it be the case that people are more lukewarm about Biden but just as committed to sticking with him?

Allow another part of Pew’s poll to answer that question.

Given the chance to answer however they wanted, more than half of Biden supporters say that the reason they plan to vote for Biden is that he is not Donald Trump. Only a fifth of Trump supporters say that it’s Biden driving their support for the president.

In other words, those Biden voters who are so committed to him are committed to him because he is not the incumbent. From Trump’s standpoint, that poses a problem. It will be quite hard to convince people who support Biden because he’s not Trump to cast a vote for Trump unless he can somehow become another human being, which seems unlikely.

This sentiment is reflected in Pew’s question about how people would respond to the results of the election. If Biden wins, three-quarters of Biden supporters say they’ll feel relieved as opposed to excited. Only a bit over a third of Trump supporters say they’d be angry.

If Trump wins? Six in 10 Biden supporters say they’d be angry.

Pew’s poll, like so many other polls of late, suggest that first outcome is more likely. The poll offers a unique opportunity, in fact, to compare current views of the race with the 2016 vote, given that Pew two years ago released validated data on how 2016 voters cast their ballots.

Among demographic groups where comparisons could be made, twice as many shifted toward Biden relative to their support for Hillary Clinton four years ago as shifted toward Trump.

The biggest shift away from Trump came from married men, who went from backing Trump by 30 points to backing him by nine. That group made up more than a quarter of voters in 2016. The biggest shift to Trump came from Hispanic Catholics, who went from preferring Clinton by 59 points in 2016 to backing Biden by 32, a 27-point shift. But it’s also a group that made up only 5 percent of the 2016 electorate.

Also noteworthy: he movement among White men without a college degree. This was a central part of Trump’s 2016 victory, their backing him by 50 points. In Pew’s new poll, that’s fallen to 33 points. Pew also asked those who’d voted for a third-party candidate in 2016 how they planned to vote this year. Among that group, Biden earns a majority of the vote, leading by 16 points.

Trump has a few months to move those numbers around, of course. But if the election comes down to how people feel about him, the result seems easy to predict.