The record number of Latinos who cast ballots for president this year are the leading edge of an ascendant ethnic voting bloc that is likely to double in size within a generation, according to a Pew Hispanic Center analysis of U.S. Census Bureau data, Election Day exit polls and a new nationwide survey of Hispanics.

The nation’s 53 million Hispanics comprise 17% of the total U.S. population, but just 10% of all voters this year, according to the national exit poll. But Hispanics’ share of the electorate will rise quickly for several reasons.