Owners of yachts big enough to have beds, toilets and kitchens can deduct the mortgage interest on their taxes even if they don't live aboard full-time, because those big yachts can qualify as second homes under the tax code.

U.S. Rep. Tim Walz thinks that's a gaping loophole for the rich, so he and two other House Democrats have introduced a bill to eliminate it.

They call their proposal the "Ending Taxpayer Subsidies for Yachts Act" because it would limit the tax deduction to those who use their boats as a primary residence.

“Closing this tax loophole restores the Mortgage Interest Deduction to its original purpose; helping middle class families realize the American Dream through homeownership," Walz said.

A 2004 study found 500,000 large boats in the U.S. qualify for the deduction, but the 2000 census found only 100,000 people living full-time on those large yachts.

Co-sponsor Rep. Mike Quigley of Illinois said: “There’s absolutely no reason why taxpayers should subsidize luxury yachts. As we work to address our budget challenges, closing this frivolous tax loophole is a no-brainer.”

The other co-sponsor, Michigan Rep. Gary Peters, said: “Homeownership is part of the American Dream and we should encourage it, but yacht owners don’t need any special handouts, especially in the middle of a budget crisis.”