Florida has 81,512 more black Democrats compared to a loss of 784 black Republicans; Louisiana has 34,325 more black Democrats, while the number of black Republicans dropped by 907; North Carolina has 92,356 more black Democrats and 2,850 fewer black Republicans.
While the number of blacks who have left the GOP for the Democratic Party can't be pinpointed, it's not hard to find voters who have made the switch.
"That's happening in a lot of places," said Ronald Walters, a University of Maryland political scientist who tracks racial trends.
In Florida, it's happening at a time when the state Republican Party has made black voter recruitment a priority - one that is more difficult with Obama's success.
Whitfield Jenkins of Ocala became a Republican nearly four decades ago, abandoning the Democrats out of anger when black voters helped elect a state lawmaker who later opposed a state holiday for Martin Luther King Jr. In 2006, Jenkins helped Republican Gov. Charlie Crist's campaign, but this year he switched back to the Democratic Party for one reason: Obama.
"Really early in his presidential campaign, when I got the opportunity to listen intently to his ideas and his platforms, I immediately said, 'This is beyond belief,'" Jenkins said. "I joined the effort and it became clear to me that I was better able to work in my community in a broad way and support this outstanding candidate as a Democrat."
Overall, Florida now has nearly 1.1 million black Democrats, compared to just under 64,000 black Republicans. Louisiana has about 704,000 black Democrats and 26,000 black Republicans, and North Carolina has more than 1 million black Democrats and just under 44,000 black Republicans.
Three other states - Alabama, Georgia and South Carolina - track voter registration by race, but voters don't register with parties. Each has seen large increases in black registration over recent seven-month periods, Georgia by almost 123,000, South Carolina by 43,198 Alabama by 20,844.
The biggest impact could be in Florida, where polls show a tight race between Obama and Republican John McCain. President Bush carried the state by only 537 votes in 2000. Democrats believe the result would have been different if not for problems in largely black precincts.
"If it's going to be a close election, it could be a huge factor," said Kevin Hill, a Florida International University political science professor. "Eighty-two thousand - that's a lot of voters."
And while Bush won by a more comfortable 381,000 votes in 2004, the Obama campaign notes that 600,000 black voters stayed home. The campaign is also targeting nearly 600,000 black Floridians who aren't registered to vote.
"You're going to see some turnout like you've never seen before in the state of Florida," said Tony Hill, a black state senator from Jacksonville who is helping the Obama campaign.
Overall, Florida has about 4.4 million Democrats, 3.9 million Republicans and 2.3 million voters who aren't registered with either party.
Florida GOP Chairman Jim Greer acknowledges that attracting more black Republicans has been difficult because of Obama's candidacy and says he doesn't expect a significant change in registration numbers this year despite party efforts to reach out to black voters.
"My goal here is that African-Americans who have voted Democratic their entire lives will begin to at least consider a Republican candidate," Greer said. "And then I'll move to the second goal of registration. But it is a slow process."
Some black Republicans say they're supporting Obama but not switching parties. They include former Florida Black Republican Council President Dorsey Miller, who helped former Republican Gov. Jeb Bush's campaigns and supports Crist.
Miller, though, said his support of Obama has nothing to do with race, but rather his dissatisfaction with the direction of the country and his concerns that McCain will continue President Bush's policies.
"It's a funny thing about Obama, but when I see him speak and see him on the stage, I don't see him as a black man, I just see a man. He symbolizes hope and we surely need hope," Miller said.
But he was quick to add that he could support another Republican for president.
"If he (Obama) stays eight years and then Jeb Bush says, 'I'm running,' I'm with Jeb."