Good report from Pew:
This gap is driven by two demographic factors—youth and non-citizenship. More than one third of Latinos (34.9%) are younger than the voting age of 18. And an additional 22.4% are of voting age, but are not U.S. citizens. As a result, the share of the Latino population eligible to vote is smaller than it is among any other group. Just 42.7% of the nation’s Latino population is eligible to vote, while more than three-in-four (77.7%) of whites, two-thirds of blacks (67.2%) and more than half of Asians (52.8%) are eligible to vote.
Yet, even among eligible voters, Latino participation rates lag those of other groups. In 2010, 31.2% of Latino eligible voters say they voted, while nearly half (48.6%) of white eligible voters and 44.0% of black eligible voters said the same.
Obviously, progressives in general and Latino groups in particular should try to work on closing that turnout gap. But I think a lot of people underestimate the extent to which these demographic factors make a difference in driving our politics. A hugely disproportionate share of the poor people in the United States are children. And a hugely disproportionate share of the poor adults in the United States are non-citizens. The fact that poor eligible voters tend not to turn out and don’t possess the social capital and money needed to impact the system through non-electoral means all make a difference. But the fundamental base on which all the other inequities are layered is the simple fact that the electorate is substantially richer than the population.