(Updated: July 2, 2009 at 2:32 PM CT)

More Americans with disabilities voted in the 2008 presidential election than in any before, a new study reveals.

In 2008, 14.7 million Americans with disabilities cast their ballots. That’s an increase of 3.8 million over the 2000 election.

The numbers come from an analysis of the U.S. Census’ Current Population Survey Voting Supplement conducted by Lisa Schur and Douglas Kruse at Rutgers University in partnership with the American Association of People with Disabilities.

While people with disabilities continue to vote at a lower rate than the rest of the population, the gap is closing, the research shows. In 2008, 57 percent of people with disabilities voted, while 64 percent of people without disabilities cast ballots.

Meanwhile, the number of people with disabilities who voted in 2008 rivals that of other minority groups, with 15.9 million African Americans and 9.7 million Hispanic voters participating.

“While the voting numbers among people with disabilities in 2008 indicates that they continue to face barriers in registration and voting, the fact that 14.7 million people with disabilities voted shows that they play an important role in the political process,” Schur says.