"But Mr. Trump’s approval rating has been stable even after seemingly big missteps."

"And if it improves by a modest amount — not unusual for incumbents with a strong economy — he could have a distinct chance to win re-election while losing the popular vote by more than he did in 2016, when he lost it by 2.1 percentage points. The president’s relative advantage in the Electoral College could grow even further in a high-turnout election, which could pad Democratic margins nationwide while doing little to help them in the Northern battleground states. It is even possible that Mr. Trump could win while losing the national vote by as much as five percentage points.... Many assume that the huge turnout expected in 2020 will benefit Democrats, but it’s not so straightforward. It could conceivably work to the advantage of either party, and either way, higher turnout could widen the gap between the Electoral College and the popular vote. That’s because the major Democratic opportunity — to mobilize nonwhite and young voters on the periphery of politics — would disproportionately help Democrats in diverse, often noncompetitive states. The major Republican opportunity — to mobilize less educated white voters, particularly those who voted in 2016 but sat out 2018 — would disproportionately help them in white, working-class areas overrepresented in the Northern battleground states...."

Writes Nate Cohn in "Trump’s Electoral College Edge Could Grow in 2020, Rewarding Polarizing Campaign/Re-election looks plausible even with a bigger loss in the national popular vote" (NYT).

That's all very interesting about the Electoral College, and if you read the whole article, you'll see a lot about polls about "approval" of Trump, which are used as a proxy for how people will vote. But in an election, you have to vote for one or another candidate (or abstain), and you might disapprove of all of them.

That is, withholding approval doesn't mean you won't vote for Trump. It's hard to approve of Trump. He's not exactly approval-seeking. You might like the results he's getting and still feel you want distance from him. You might vote for him because you want more of the same or because you think his opponent will take away some of the things you like and still be able to say that you "disapprove" of the person known as Trump.

A conscious sense of disapproval may even facilitate a vote for Trump. People who seek approval for themselves may find it expedient to express disapproval of Trump — to be free of the onus and stigma of approving of him — but when the time comes to answer the question whether they want 4 more years of his work, they might also find it expedient to say "yes."