Harvard just released a poll that should give Trump's campaign heartburn

One of the wildcards in the 2020 presidential election will be turnout among young voters -- and one poll released by the Institute of Politics at Harvard Kennedy School shows that President Donald Trump has reason to worry.

The poll has found "historic interest in the upcoming election" among voters between the ages of 18 and 29, as 63 percent of these voters say they will "definitely" be voting this year, up from just 47 percent who said the same at this time in 2016.

What's more, the poll found that these voters are going overwhelmingly for Democratic presidential nominee Joe Biden, who leads Trump by 63 percent to 25 percent among the voters most likely to go to the polls.

Although there has been some worry about Biden not having high favorable numbers with young voters, the Harvard poll shows he's significantly increased his standing with them since the spring.

"Joe Biden is viewed favorably by 47 percent of all young adults, compared to 41 percent who view him negatively," the Institute of Politics explains. "This is an increase compared to our Spring poll where only 34 percent of all young adults viewed Biden favorably and 47 percent who viewed him negatively."

The last time young voters were this engaged in an election, the poll notes, came in 2008 during former President Barack Obama's first presidential campaign.