A bipartisan group of lawmakers is pushing to expand how many vehicles from each manufacturer are eligible for federal electric vehicle tax credits, despite opposition from some Republicans who want to abolish the practice.

Since 2008, up to 200,000 vehicles per manufacturer qualify for a $7,500-per-vehicle tax credit for electric and plug-in hybrid vehicles. The subsidy is reduced every six months until entirely eliminated after manufacturers hit the cap. So far, Tesla Inc. and General Motors have already hit the 200,000 cap, causing a reduction in the tax credit for consumers.