Cotton's first TV ad hits Pryor on ObamaCare

"What's good for the goose ought to be good for the gander, but not in Washington. Mark Pryor cast the deciding vote to make you live under ObamaCare, but Pryor votes himself and everyone in Congress special subsidies so they're protected from ObamaCare," the ad's narrator says. "Exemptions and special subsidies for Mark Pryor, higher insurance premiums for you. Mark Pryor: Voting with Obama, voting against Arkansans like you."

Republicans have sought to make hay out of subsidies congressmen and congressional staffs receive under ObamaCare, given because congressional staff are the only employees of large organizations that the law requires to participate in healthcare exchanges. Cotton recently joined Republican National Committee Chairman Reince Priebus to push a similar line of attack.

Pryor's campaign fired back against the ad, attacking Cotton's record.

"Only Congressman Cotton is arrogant enough to think that Arkansans won't see his blatantly false political attack for what it is: a weak attempt to distract from his irresponsible votes to gut Social Security and Medicare, kill the Farm Bill and end affordable student loans on behalf of his Washington special interest handlers," Pryor spokesman Erik Dorey says.

Pryor is viewed as the most vulnerable incumbent senator running for reelection next year, and if Republicans hope to retake the Senate his seat is likely a must-win.