The estate tax came a step closer to being revived late today when the Senate defeated a move to permanently repeal it.

But foes of the tax hope to use it to score more success in the fall elections.

The estate tax disappeared for 2010, in one of the final steps of President George W. Bush’s 10-year tax-cut measure. But next year, when the Bush tax cuts expire, the estate tax springs back to life — at its pre-2001 level of 55%.

Wednesday’s amendment to repeal the estate tax was offered by Sen. Jim DeMint (R., S.C.), in the midst of debate on a bill to extend jobless benefits. The amendment failed by a wide margin of 39-59. The vote was almost entirely on party lines, although two Democrats – Sens. Blanche Lincoln of Arkansas and Ben Nelson of Nebraska – joined Republicans in voting “yes.”

Other Democrats criticized Republicans for supporting estate-tax repeal that would benefit the well-to-do, while withholding support for extended unemployment benefits if they aren’t offset with budget savings elsewhere.

The estate tax has lost a little of its luster for Republicans in the wake of the economic downturn; a bipartisan effort in Congress to lower future estate tax rates has largely gone quiet for now, as lawmakers focus on keeping the economic recovery alive.

But the estate tax –- or “death tax,” as critics term it -– remains an emotional issue for some voters. In the current antitax environment, it could become a sleeper issue in some races, including Senate Majority Leader Harry Reid’s re-election bid in Nevada.

Estate-tax opponents view Reid as a main obstacle to estate-tax relief. They’ve been eyeing his race as one where the estate tax could help persuade small-business owners. Reid’s opponent, Sharron Angle, signed a pledge this week to work for repeal.