Washington (CNN) -- The Democratic-controlled Senate on Wednesday rejected two proposed versions for a balanced budget amendment to the Constitution -- a setback to GOP leaders and conservative activists who say the measure is necessary to end the federal government's spiraling deficit spending.
A Democratic version opposed by Republicans fell on a 21-79 vote. Then a Republican version also failed to get the two-thirds majority required with a 47-53 vote.
Last month, the Republican-controlled House of Representatives failed to pass a GOP-proposed amendment, falling 23 votes shy of the two-thirds majority required for passage.
The congressional votes on the amendment were agreed to by both parties in August as part of the agreement raising Washington's debt ceiling.
Democratic leaders, however, are vehemently opposed to the idea, arguing that it would force the government into an economically destructive cycle of massive spending cuts.
Sen. Dick Durbin, D-Illinois, said Wednesday that a step as historically significant as a constitutional amendment was unnecessary.
Getting government spending under control "takes political will, even political courage," Durbin said, but "it doesn't take a constitutional amendment.''
Conservative Republican Sen. Orrin Hatch of Utah disagreed, saying Congress has repeatedly proved it's unable to control itself on spending.
"We are taxing and spending this country into bankruptcy," Hatch said, later adding, "We don't have any restraint around here."
Despite the proposal's defeat, it has been favored by the public. Nearly three in four Americans favored passage of the amendment in a July 18-20 CNN/ORC International Poll, while 24% were opposed.
Sixty percent of Americans say they believe a balanced budget amendment is necessary to get the deficit under control, according to the poll.
The House passed a balanced budget amendment in 1995, but the measure fell one vote short in the Senate in both 1995 and 1997.