WASHINGTON (CNN) -- A new Census Bureau report provides more evidence that the changing demographics of the United States are having a deep impact at the voting booth.

The report on the 2012 election found that for the first time on record, black voters turned out to the presidential polls at a higher rate than whites. More than 66% of eligible blacks voted in the presidential contest that pit President Barack Obama against Republican nominee Mitt Romney. Only 64.1% of whites turned out to vote.

The report was released Wednesday.

This the first time since 1968 that blacks turned out at a higher rate the whites.

In addition to blacks turning out at a higher rate, the number of Asian and Hispanic voters grew from 2008 to 2012. Hispanics added 1.4 million people and Asians added over 500,000. Between 1996 and 2012, blacks, Asians and Hispanics all saw their percentage of the voting population increase.

"Over the last five presidential elections, the share of voters who were racial or ethnic minorities rose from just over one in six in 1996 to more than one in four in 2012," said Thom File, the report's author.

The highest turnout of blacks, in addition to the growing number of Hispanics and Asians, could also explain Obama's success in defeating Romney.

According to CNN exit polls, 93% of African-Americans, 71% of Hispanics and 73% of Asians supported Obama over Romney.