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The number of millennials is skyrocketing

But other age groups are more likely to vote

CNN  — 

No wonder Bernie Sanders is getting a boost at the polls: Millennials are now a voting force to be reckoned with.

Some 69.2 million Millennials are eligible to vote, roughly equal to the 69.7 million Baby Boomers who can cast a ballot, according to a new Pew Research Center report.

The number of voting-eligible Millennials, those between 18 and 35 this year, has more than doubled over the past decade as the generation has grown into adulthood.

Both Millennials and Baby Boomers account for about 31% of Americans who can vote, though the number of Baby Boomers, who are ages 52 to 70 this year, has been declining since its 2004 peak of 72.9 million. Gen Xers, who are between 36 and 51 years old, number only 57 million, or 25% of the electorate.

Millennial Democrats have lined up solidly behind the 74-year-old Sanders this election season, while older voters have gravitated to front-runner Hillary Clinton, 68, according to exit polls of primary voters.

Some 68% of Americans age 18-34 have a favorable opinion of Sanders, versus 48% for Clinton and 25% for presumptive Republican nominee Donald Trump, according to a CNN/ORC Poll released in May.

Clinton tries to get the millennials on board

Millennials are much less likely to vote than Baby Boomers or Gen Xers, according to Pew. Even in 2008, when President Barack Obama brought out younger voters in droves, only half of eligible Millennials cast a ballot.

Younger Americans are typically less likely to vote than their parents and grandparents. But voter turnout among young adults often depends on more than just demographics, according to Pew. It is also affected by the candidates, voter mobilization efforts, the state of the economy and satisfaction with the direction of the country.

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“While it might be a ‘slam-dunk’ that millennials soon will be the largest generation in the electorate, it will likely be a much longer time before they are the largest bloc of voters,” wrote Pew Senior Researcher Richard Fry, who authored the report.