WASHINGTON (AP) -- Though threatened by a White House veto and an almost certain death in the Democratic-controlled Senate, the House passed a Republican-backed business tax cut on Thursday with a mostly party-line 235-173 vote.

The $46 billion measure, by House Majority Leader Eric Cantor, R-Va., would provide a one-year, 20 percent tax deduction for companies with fewer than 500 workers. That means firms could generally subtract 20 percent from their domestic incomes before calculating the federal taxes they owe.

"This is straight-up something to help small businesses keep more of their money while they're having so much difficulty keeping the lights on, and instead giving them the ability to grow," said Cantor.

Democrats argued that the bill was too unfocused, providing the tax cut if a company hired no new employees or even if it fired some. They also complained that it was too generous to wealthy individuals owning small firms and to extremely successful businesses.

The Associated Press contributed to this report.