Millennials (those ages 18 to 35 in 2016) reported casting 34 million votes last November, a steep rise from the 18.4 million votes they cast in 2008. But, despite the larger size of the Millennial generation, the Millennial vote has yet to eclipse the Gen X vote, as 35.7 million Gen Xers (ages 36 to 51 in 2016) reported voting last year.

It is likely, though not certain, that the size of the Millennial vote will surpass the Gen X vote in the 2020 presidential election. The Millennial generation as a whole is larger than Gen X (both in absolute size and in the number of birth years it spans). In addition, the ranks of the nation’s Millennials are growing faster than older generations due to immigration, which is likely to be accompanied by increased naturalizations. As a result, Millennials are likely to be the only adult generation whose number of eligible voters will appreciably increase in the coming years.

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The ascendance of the Millennial vote is noteworthy because Millennials are more likely to be self-described independents, but they also are more Democratic than older generations in their political preferences. Among Millennials, 44% were independents in 2016, compared with 39% of Gen Xers and smaller shares of Boomers (31%) and members of the Silent Generation (23%). At the same time, Millennials lean to the Democratic Party to a much greater degree than other generations. In 2016, 55% of all Millennials identified as Democrats or Democratic-leaning independents, while just 33% identified as Republicans or GOP-leaning independents. By comparison, 49% in Generation X, 46% of Boomers and 43% of members in the Silent Generation identified with or leaned Democratic. And on issues such as marijuana legalization and same-sex marriage, Millennials take more liberal positions than those in older generations.