Washington (CNN) More young Americans are saying they will vote in the upcoming midterm elections than in the last two midterms, according to a new national poll released Tuesday by the Harvard Kennedy School's Institute of Politics.

Thirty-seven percent of Americans under 30 say they definitely plan to vote in November, a significant jump from the 23% who said the same in 2014 and 31% in 2010.

The survey, which included more than 2,500 responses from 18- to 29-year-olds, found that young Democrats are driving the surge in enthusiasm. Fifty-one percent say they will definitely vote this fall compared to just 36% of Republicans.

This is a significant reversal from the last election cycle in 2014, where young Republicans were more excited about the midterm elections. Nearly 70% say they want Democrats to take back control of Congress in 2018.

When it comes to the current administration, young voters overwhelmingly disapprove of Trump's job performance, a factor that's likely influencing the shift in enthusiasm. They also continue to express distrust in major institutions: just 17% say they trust Congress all or most of the time, while 16% say the same about the media. The Supreme Court fared better at 43%.

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