WASHINGTON (CNN) -- Rep. Harold Ford Jr. suggested Sunday night that former Chattanooga Mayor Bob Corker knew about a Republican National Committee's television advertisement that sharply criticizes Ford and implies he parties with Playboy playmates.

Corker denied he knew the RNC was going to run the ad and reiterated his call for the committee to pull the ad down. "We think the ad is tacky, we think it's not senatorial," Corker said in an interview with CNN's Carol Lin. "We think it has no place in this race."

Federal campaign finance laws prohibit campaigns from communicating with independent expenditures made by party committees.

But Ford, appearing on the same program, said an RNC staffer works hand-in-hand with the Corker campaign. "The young lady that works for the Republican National Committee actually travels with my opponent wherever he goes," Ford said. "Now, I don't know if they talk or not, but they ride in the same car."

An RNC spokeswoman said there are no plans to stop running the ad.