A bipartisan group of lawmakers plans to introduce a bill to expand federal tax credits for buyers of electric vehicles, in what could be a boon for the growing EV market.

The existing $7,500 tax credit for buyers of EVs phases out over 15 months once an automaker sells 200,000 electric cars. The tax credit for Tesla buyers was halved to $3,750 on Jan. 1; General Motor's tax credit was likewise cut in half starting April 1.

The bill, dubbed the Driving America Forward Act, would grant each automaker a $7,000 tax credit for an additional 400,000 vehicles after it exhausts the first 200,000 vehicles eligible for tax credits. It would shorten the phase-out schedule to nine months. The credits are paid directly to consumers, who can write them off on their tax returns.

"At a time when climate change is having a real effect on Michigan, today's legislation is something we can do now to reduce emissions and combat carbon pollution," Sen. Debbie Stabenow, D-Mich., one of the sponsors of the legislation, said in a statement. "Our bill will help create American jobs and cement Michigan's status as an advanced manufacturing hub."

Tesla shares rose 1.6 percent in morning trading Wednesday on the news.

Sens. Gary Peters, D-Mich., Lamar Alexander, R-Tenn., and Susan Collins, R-Maine, and Rep. Dan Kildee, D-Mich., signed on to the bill.