The measure would not reach balance, but it would undo automatic budget cuts that started taking effect this month and largely leaves alone rapidly growing benefit programs like Medicare.
Thursday's measure would ban the sale of 157 kinds of semi-automatic weapons, guns that automatically reload, and large-capacity ammunition magazines carrying more than 10 rounds.
The measure, misleadingly named the Employee Free Choice Act, would let a union win automatic recognition simply by cajoling a majority of employees to sign cards.