Pollster Dan Cox said on Monday that "antipathy towards [President] Trump" could be one of the top factors driving millennials to the polls in Tuesday's midterm elections.

"If you look at a lot of the issues, whether it's gun control or climate change, they're not rising to the top, and then health care is not as big of an issue for young people as it is for seniors, so there's not one issue that has been galvanizing for this generation," Cox, research director at the Public Religion Research Institute, told Hill.TV's Joe Concha on "What America's Thinking."

"So it may just be antipathy towards Trump," he said.

Democrats are hoping for a blue wave that includes millennials as they seek to take back the House and Senate.

Recent polling shows that millennials, who tend to not vote in big numbers during midterms, are likely coming out in larger numbers in Tuesday's contests.

An NBC News/GenForward survey released last week found that a third of voters ages 18-34 said they would definitely vote in the midterm elections.

Trump has low approval ratings with millennials, which could end up boding well for Democrats.

A recent survey from Harvard's Institute of Politics found that Trump's approval rating among millennial voters was at 25 percent.

— Julia Manchester