Sen. Claire McCaskill (D-Mo.) has sold the private plane she and her husband co-owned, hoping to put an end to what has become the favorite attack line of her opponents.

McCaskill's congressional office said the plane was sold for $1.9 million to an air ambulance group. McCaskill took a loss on the plane's sale.

“Claire said she would sell the plane and did. True to her word as always," McCaskill spokesman Trevor Kincaid said.

The saga over the airplane dates back to the beginning of the year, when McCaskill was accused of using congressional funds to pay for a trip on the airplane that had a political purpose. The Senate Ethics Committee dismissed the complaint, but McCaskill announced she was reimbursing the government about $300,000 for back taxes she had failed to pay on the plane.

Calling the tax issue a substantial yet unintentional mistake, McCaskill vowed in April to "sell the damn plane."

Republicans seized on the gaffe as a symbol that McCaskill was out of touch with constituents, launching a mocking "Air Claire" ad campaign and arguing she had undercut her own claim to be an ethics leader.

Although McCaskill is fighting a difficult reelection campaign in a state that has soured on President Obama and Democrats, the airplane fiasco does not seem to have hurt her significantly with Missouri voters. She has maintained a small lead in the polls against all of the Republicans vying to unseat her in 2012.