The House was moving toward passage Wednesday of a bill that would revive or extend about $55.5 billion in tax breaks for individuals and businesses for one year.

The bill also contains some new breaks to help low-income families, homeowners and trial lawyers. A final vote was expected by late afternoon.

The bill does not include a one-year “patch” for the alternative minimum tax, a provision Congress is expected to enact later this year. That — and the House’s insistence on revenue-raising offsets — make the measure’s future murky in the Senate.

On Wednesday morning, the White House issued a veto threat against the bill in its current form, complaining about the offsets and several other provisions, including a temporary new standard deduction for property taxes.

The most costly of the bill’s provisions include the research and development tax credit, an optional deduction for state sales taxes, and accelerated depreciation for certain retail stores and restaurants. All of those provisions expired at the end of 2007.

The bill also would extend certain tax breaks that expire in December.

To help win support in the Senate, the House package includes $18.5 billion in energy-related tax breaks, several of which enjoy strong support among Senate tax writers.

The energy provisions, including extensions of expiring tax breaks for wind and solar energy, have been in limbo for the past year because of a House-Senate fight over offsets. Some of the energy provisions would get longer extensions, but the main wind credit would be restored only through the end of 2009.