The measure, titled the Middle Class Tax Relief and Job Creation Act of 2011, also delays cuts in Medicare reimbursements for doctors.
The bill likely will come up for a vote next week, The Hill reported, but its provision fast-tracking the Keystone XL oil sands pipeline from Canada is opposed by the White House, which wants the pipeline decision put off until next year.
Senate Majority Leader Harry Reid, D-Nev., issued a statement Friday criticizing the Keystone provision, saying now isn't the time to debate issues unrelated to the payroll tax and unemployment benefits.
Unless Congress acts, the 2 percentage point reduction in Social Security payroll taxes enacted for 2011 will expire Dec. 31, going back to 6.2 percent of earnings, effectively raising taxes an average $1,000 a year for working Americans. Senate Democrats had proposed lowering the tax to 3.1 percent and extending a lower rate to employers as well.
The White House issued a statement, criticizing the bill.
"Republican leaders in Congress are still playing politics at the expense of middle-class families," White House spokesman Jay Carney read during the daily press briefing. "Their proposal breaks the bipartisan agreement on spending cuts that we reached just a few months ago and makes harmful cuts to things like education that strengthen middle-class security.
"Their plan seeks to put the burden on working families while giving a free pass to the wealthiest and big corporations by protecting their loopholes and subsidies. ...
"As one leading Republican said -- you probably saw this in the newspaper -- quote, 'Frankly, the fact that the president doesn't like it makes me like it even more.' That is precisely why Americans are fed up with Congress."
The GOP bill also tries to gut healthcare reform and weakens air pollution rules for industrial boilers and incinerators, The Hill said.
The bill follows several bills produced by Senate Democrats and rejected by Republican filibusters.
The measure seeks to pay for the extended tax cut and added unemployment benefits, with their $175 billion and $180 billion price tags, by cutting back on social-program benefits, selling federal assets, freezing federal employees' pay and cutting the number of federal workers by about 10 percent through attrition, The New York Times said.
The Senate Democrats' bills, supported by Obama, would pay for the tax-cut extension by raising taxes on people earning more than $1 million a year.