Former Democratic Senate candidate Andrew Romanoff is asking donors to help cover his campaign debt.In a letter to supporters, Romanoff said his campaign did incur a debt."I need your help to retire it," said Romanoff. "The most you can contribute is $2,400. That limit includes any money you gave us during the primary."Romanoff didn't say how much debt he has.Romanoff sold his Denver home during the campaign. In his e-mail he said, "I don't need an air mattress, a futon, a spare bedroom or a basement. Neither does my dog. We have gotten a lot of kind offers -- which I appreciate very much -- but we're not out of our house yet." He didn't explain what that means.Romanoff lost to incumbent Sen. Michael Bennet 46 percent to 54 percent."I knew the path would not be easy," Romanoff said about his decision to run for Senate. "I am and always will be grateful to the friends who joined me along the way."Romanoff said he is planning one more event for supporters next week: a thank-you party.