It's taken about a year, but thanks to new Census numbers and to Project Vote, we now have the most accurate picture of who voted, who didn't vote, and how the voting patterns compare to previous elections.  The highlights: 64% of the 204 million voting-age Americans voted, up about 6 million in number and 4 percentage points from 2004.  Historically underrepresented groups made gains in this election.  Non-whites made up more than 90% of the increase in the total number of voters.  The authors conclude that had non-whites voted at the same percentage as whites, more than 5 million more votes would have been cast in 2008.  The study, by Douglas Hess and Jody Herman, finds that had voters under 30 voted at the same rates as their counterparts over 30, more than 7 million additional ballots would have been cast.

No wonder Republicans worry about a Democratic demographic storm.  Young voter turnout has increased at a rate of about 30% per general election since 2000. Indeed, the rate of increase was higher from 2000 to 2004 than from 2004 to 2008.  Women turned out at a higher rate than men.  Black men under 30 saw their participation rates increase by eight percentage points, Latino women and women under thirty grew by 6% and Asian women saw their participation rates grow by 13 points. Young black women voted at the highest rate among voters under 30 -- and the only turnout rate that exceed the voting rates by white people of any age.  White women under 30 voted at a rate of 52% -- higher than all but black women under 30.

Women outvoted men by 10 million; the rates of unmarried women and unmarried women are growing faster than their married counterparts, other variables held constant. Twenty million more people voted in 2008 than in 2000; unmarried women composed about 35% of the increase; unmarried men composed about 29%.  Despite all this, unmarried folks remain underrepresented.

No wonder Democrats worry about an off-year election. Not only does turnout itself drop -- usually about 15 percentage points through all demographic cleavages -- but it drops even higher for new voters and for younger voters.

No wonder Democrats and affiliated interest groups spent so much time trying to register the  young, the poor, the non-white -- and why this registration effort has become a political football. ACORN's voter registration arms tend to ferret out non-voters in communities that redound to the benefit of the Democratic Party.

For the first time in recorded memory, voting rates for those under 30 increased; voting rates for those over 30 did not.

Among the unregistered or non-voting, non-whites made up a disproportionate percentage of this group.  Latinos are still the most significantly under-registered group, making up 13% of the total number of unregistered adults and just 7% of the total number of voters.  There remains a lingering mistrust of voter registration efforts in parts of the Latino community, and there's a large number in this sub-group who are undocumented, making outreach efforts difficult and fraught with political controversy too.

Among income, about 30% of those making less than $25,000 a year were not registered to vote, compared to just 13% of those making more than $100,000 a year.

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