WASHINGTON (AP) — National Democrats are pumping $320,000 into congressman Chris Murphy's Senate campaign in Connecticut in hopes of blunting former pro wrestling executive Linda McMahon's momentum.

With polls showing a tight race in the Democratic-leaning state, Murphy launched a new TV ad Wednesday after the Democratic Senatorial Campaign Committee's cash infusion. The ad accuses his Republican opponent, the former chief executive of WWE, of laying off workers while her company got millions in tax credits. McMahon denied the charge.

McMahon enjoys a strong money advantage over Murphy. She spent $50 million of her own money on a failed Senate run in 2010. She has lent or given nearly $16 million to her 2012 campaign. Murphy has raised less than $6 million.