‘There Were Signs’: How the Polls Anticipated Some of Trump’s Key Gains

As the votes were counted and the races called, local Democrats had a decent showing last week in Passaic County, N.J., where 43 percent of residents identified as Hispanic in the 2020 census. The party swept the races for U.S. Senate, sheriff and county commissioners.

But one Democrat didn’t do as well: Kamala Harris. In the same county that Joe Biden carried by 17 percentage points, and Hillary Clinton by 23, Donald J. Trump is currently leading by three points. There are still some ballots to be counted, but it’s a clear departure from the definitive win of the past two Democratic nominees.

“I was astonished,” said Sean Trende, the senior elections analyst at RealClearPolitics. “I didn’t see that coming miles away. I knew he was going to do well with Hispanic voters. But I didn’t expect that.”

It was always on the table for Mr. Trump to sweep the swing states as he sailed to victory last week. But he also racked up many other successes, making modest but important gains among Hispanic voters, Black voters and voters in urban districts, including big, Democrat-dominated cities like New York and Chicago.

Some of those gains may have been surprising, even to election analysts. But to a great extent, the pre-election polls had it right. Not only did they correctly suggest that the presidential race would be close overall, but they also anticipated Mr. Trump’s inroads among groups that typically tilt heavily toward Democrats.

“When you look at how Hispanic Americans voted, how younger Black men voted, and some other things, it ties in with the trends that we were seeing,” said Lydia Saad, a senior editor for the Gallup Poll. “Did we see this coming? The answer to a lot of it is yes.” She added, though, that there had been an open question heading into Election Day of whether Ms. Harris could claw back some support from these groups.