President Trump can still win the 2020 election. But doing so increasingly looks as though it will require either a massive polling error, one larger than some states saw in 2016 — or some nondemocratic effort to sway the results. Even such machinations, though, would probably leave an awful lot of Republican candidates stranded.

On Wednesday afternoon, CNN released a national poll conducted with its partners at SSRS. It was unremarkable in general, giving former vice president Joe Biden a double-digit advantage over Trump. But that, of course, is remarkable for the final days of a presidential race. If it holds, it’s hard to see how Trump could cobble together the electoral votes he needs to win.

The 12-point overall margin is 7 points larger than the advantage the last CNN poll of 2016 gave Hillary Clinton, then Trump’s opponent. (The actual margin on Election Day was about 2 points.) Trump is faring about as well with men as he did four years ago in CNN’s poll but doing twice as badly with women. Older voters, those 65 and up, prefer Biden by double digits, though CNN’s last poll in 2016 showed Clinton with an advantage among that group that didn’t materialize, according to Pew Research Center’s assessment of the 2016 electorate.

Whites without a college degree (called “White, non” for the sake of brevity below) preferred Trump by 30 points over Clinton — but only 18 over Biden.

That, by itself, is a significant shift. The reason for it is pretty obvious: Voters simply like Biden better than they did Clinton. Overall, the percentage of people who viewed Trump favorably in late 2016 was only 5 points less than the percentage who viewed Clinton favorably. Now, though, he trails Biden by 11 points on that measure. In each of the demographic groups identified above, Trump is viewed about the same way he was in CNN’s last 2016 poll, while Biden is viewed better than Clinton: 5 points more among men, 7 among women, 9 among those 65 and over, and 8 among non-college-educated Whites.

Positive views of Biden are one factor, but so are negative views of Trump. Trump voters told CNN that they’re voting for him mostly because they like him. Biden voters were evenly split: About half said their vote was because they liked Biden, and about half said it was because they didn’t like Trump.

In other words, one might assume that, were the Republican candidate not Trump, the top of the ticket for the party might be faring a bit better. Perhaps a lot better.

That’s important when we consider the generic congressional ballot question by CNN: Respondents are asked whether they plan to vote for the Democrat or the Republican in their local congressional race. Respondents told CNN that they prefer the Democrat in that contest by a 54 percent to 42 percent margin — the exact same numbers by which Biden leads Trump.

Across the groups we’ve been looking at, the split on the congressional ballot was about the same as the split on the presidential race. Men are about evenly divided between the parties on both questions. Women strongly prefer the Democrats. Older voters do, too. Whites without college degrees prefer the Republicans.

There are definitely causality questions here. Which is to say, it’s not clear whether partisanship is driving views of both the congressional race and the presidential one, meaning that the people at the top of each party’s ticket might not matter much. It seems more likely, though, that Trump’s presence is driving views of his party generally. That opposition to the president is pushing down his numbers against Biden and, then, his party’s candidates’ numbers, too.

It’s always been the case that the presidential contest would probably end up as a referendum on Trump. He’s simply too polarizing — and too unwilling to step out of the spotlight — for it not to be. It was not necessarily the case, though, that his party would stand alongside him on the deck of this particular cruise ship as it sails through iceberg-choked waters. Yet it is, rearranging the deck chairs.

Again: Trump could win. We learned in 2016 to be wary about saying “never,” and we learned in 2020 that any black-swan event that could occur just might. But if you’re a Republican in a difficult congressional contest, it wouldn’t hurt to start securing some moving boxes.