The youngest Americans — millennials and Generation Z — are set to exercise their political muscle in 2020, making up 37% of the electorate, according to a new study by Pew Research.

Why it matters: Younger generations are by far more racially and ethnically diverse and are more likely to be Democrats. But baby boomers remain the generation with the largest share of the voting-eligible population — though barely — and older generations have historically been more likely to turn out and vote.

In 2016, for example, boomers and other older generations accounted for 43% of eligible voters, but cast 49% of the ballots.

The big picture: For the first time, millennials will make up a smaller share of the electorate than they did in the last presidential election, even as the generation's numbers continue to grow due to immigration.

Yes, but: Generation Z is set to make up more than 10% of the 2020 electorate, surpassing the elderly Silent Generation for the first time. These youngest Americans have continued and deepened many of the political trends favored by millennials, and they are expected to be almost half non-white.

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