From the press release:
About 131 million people reported voting in the 2008 U.S. presidential election, an increase of 5 million from 2004, according to a new table package released today by the U.S. Census Bureau. The increase included about 2 million more black voters, 2 million more Hispanic voters and about 600,000 more Asian voters, while the number of non-Hispanic white voters remained statistically unchanged.
Additionally, voters 18 to 24 were the only age group to show a statistically significant increase in turnout, reaching 49 percent in 2008 compared with 47 percent in 2004. Blacks had the highest turnout rate among 18- to 24-year-old voters — 55 percent, an 8 percent increase from 2004. The increased turnout among certain demographic groups was offset by stagnant or decreased turnout among other groups, causing overall 2008 voter turnout to remain statistically unchanged — at 64 percent — from 2004.