Less than 15 minutes into the event, held in front of a large crowd gathered at the University of Tennessee at Chattanooga, Ford was forced to defend the number of votes he'd missed in Congress while campaigning. He declared his overall voting attendance record to be 93 percent, adding, "I don't know about schools here in Chattanooga, but that's a pretty good grade where I come from in Memphis."
Ford later hit back at Corker, accusing him of hiring four illegal aliens at a work site that was raided. Corker responded that 18 years ago, a subcontractor — "one of thousands" — had four employees that worked for them.
The two continued to trade barbs as they battle to fill the seat being vacated by retiring Senate Majority Leader Bill Frist. Recent polls show a dead heat between the candidates. The outcome of the election could determine whether Democrats take control of the Senate.
The debate ended tensely with Corker questioning Rep. Ford about his relationship with his father, a former congressman. Corker noted that Ford's father was a lobbyist for Fannie Mae when the younger Ford served on the House Financial Services Committee.
Ford responded that no one in his family has ever lobbied him, and said he would refuse them if they did. He also took issue with Corker's questioning. "Attacking my father has no place in this campaign," he said.
Ford later told WEDF-TV that Corker's comment was the same as accusing his father of being a crook. Corker said it wasn't meant to be disparaging.
Corker and Ford's final debate will be Oct. 28. Corker is a former mayor of Chattanooga. Ford, a representative from Memphis, would be the first black U.S. senator from the South since Reconstruction.
The Corker campaign has tried to make Ford's prominent Memphis political family an issue in the race. Ford has expressed support for his family and tried to steer attention back to policy issues.
The two differ on approaches to Iraq. Ford has proposed decentralizing the country along religious and ethnic lines, while Corker has said "the commanders on the ground" should determine its direction.
Ford's campaign is pressing Corker on what appeared to be a contradiction in expressing his thoughts on the most appropriate course of U.S. action in Iraq.
Corker said during a Republican primary debate in Memphis in July that the U.S. should "stay the course" in Iraq. During their first debate last Saturday in Memphis, Corker denied ever using the phrase.
Corker's campaign acknowledged the former Chattanooga mayor had have used the phrase "stay the course," but that he never intended that to mean the U.S. should keep the status quo.
"Bob Corker has the courage of no one's convictions," Ford senior adviser Michael Powell said in a statement. "Instead of taking responsibility for backing a failed approach in Iraq, he has resorted to twisting words beyond their plain meaning. Tennesseans know what 'stay the course' means, and they know that Bob Corker isn't playing straight with them."
Both candidates have said they want to control government spending, clamp down on illegal immigration and reduce the country's dependence on foreign oil.
In recent days, both candidates' campaigns have faced embarrassing disclosures.
The Commercial Appeal in Memphis reported that Corker lost more than $1 million in a joint Internet investment with a Memphis venture capital firm and then played a role while mayor in getting Chattanooga's employee pension fund to invest in the firm.
Corker was a joint investor with Delta Capital Management in an Internet business called Freeliant.com, which started in 2000. Freeliant foundered and collapsed in 2002, taking with it about $4 million in investors' money.
Later as mayor in 2004, Corker met frequently with officials at Delta and encouraged them to develop a presence in the Chattanooga area, the newspaper reported.
Federal election records show that an executive with Delta has contributed money to Corker's Senate campaign.
Corker denied playing a role in the city pension board's decision to invest $1 million with Delta. He said he didn't even attend the January 2004 meeting when the board voted to do so.
"I never went to any of the meetings to make the (pension) allocations, nor did I try to influence people in that regard," said Corker, who has been praised for reforming pension investments as mayor.
Meanwhile, in a Ford campaign TV ad, a woman identified as Dixie Taylor Huff says she was asked, "What in the world is a country girl like you doing for Harold Ford Jr.?" What the ad doesn't say is that until last year, Huff was the treasurer of the state Democratic Party.
Powell says there's nothing misleading about Huff's role in the commercial, adding that a lot of rural Tennessee residents are supporting Ford — and that's the point of the commercial.