"Time makes it more complicated," he said in an interview, asked if he thought there still would be enough Republican support to pass the measure. "I do," he said.

The cost of renewing expanded jobless benefits would be covered by extending so-called pension smoothing, which was set to phase out this year. That maneuver would give companies more time to make payments to pension funds, meaning short-term taxable income would rise as they claim fewer deductions.

Other offsets include extending customs user fees through 2024 and allowing single-employer pension plans to prepay their flat-rate premiums to the Pension Benefit Guaranty Corp.

Obama Pressing

President Barack Obama has pressed lawmakers for months to reach a compromise on extending the aid. The measure agreed to by senators would be retroactive to Dec. 28, when the emergency benefits expired for about 1.6 million Americans.

The Congressional Budget Office said in a preliminary estimate that the emergency benefits would cost almost $9.9 billion while cutting the deficit by almost $9.4 billion through 2019. That's because prepayment of Pension Benefit Guaranty Corp. premiums would generate almost $18.4 billion in extra revenue over the next five years.

The last time Democrats tried to act on this issue, they pressed for three months of benefits. The bill, S. 1845, stalled when backers didn't have enough support to cut off debate. The Feb. 6 vote was 55-43.

Co-sponsors of the compromise measure include Republicans Susan Collins of Maine, Rob Portman of Ohio, Lisa Murkowski of Alaska, and Mark Kirk of Illinois, and Democrats Jeff Merkley of Oregon, Cory Booker of New Jersey, Sherrod Brown of Ohio and Majority Whip Dick Durbin of Illinois.

House Speaker John Boehner of Ohio has said the House would consider extending unemployment benefits only if the Senate offsets the cost with budget savings and included measures to promote job creation.