Crossroads spends big in NC to defend Romney

Conservative superPAC American Crossroads is spending big in NC to defend Mitt Romney.

The 527 announced today it's made an $893,000 NC ad buy for a new attack ad titled "Smoke," blasting President Barack Obama for his negative ads against the GOP candidate. 

Romney has been on the ropes for more than a week over allegations relating to his tenure at Bain Capital, and for declining to release his tax returns for years preceding 2010, despite calls for their disclosure from leading conservatives. 

"What happened to Barack Obama?" says the ad's female narrator. "The press and even Democrats say his attacks on Mitt Romney's business record are misleading, unfair, and untrue - blowing smoke."

The ad accuses Obama's campaign of attacking Romney because the president "can't run on" his record. 

Crossroads says the new ad will run for eleven days in nine swing states, including NC. The total ad buy is a whopping $9.3 million on broadcast TV and internet.