The vote clears the way for another Senate vote on the estate tax, following the Senate's rejection of repeal earlier this month.

An ad advocating the tax features Paris Hilton as a likely beneficiary of the repeal. The media and lobbying efforts are strongest in states represented by senators whose votes will determine the outcome. They include Democrats such as Louisiana's Mary Landrieu, Oregon's Ron Wyden, Montana's Max Baucus and Indiana's Evan Bayh, as well as Republicans such as Arizona's John McCain and Ohio's George Voinovich.