The Senate on Thursday overwhelmingly approved an amendment banning reinstatement of the so-called "Fairness Doctrine" that would threaten conservative talk radio. Republican Sen. Jim DeMint of South Carolina attached the amendment, called the Broadcaster Freedom Act, to a bill giving the District of Columbia a voting representative in the House. It passed by a wide margin of 87-to-11. But it's not clear if the amendment will survive as Congress debates the voting rights bill. Democratic Sen. Dick Durbin of Illinois also won approval for an alternate amendment ordering the Federal Communications Commission to encourage radio ownership "diversity." It passed by a vote of 57 to 41. A DeMint aide said Durbin's measure will "impose the Fairness Doctrine through the back door by trying to break up radio ownership,” Fox News reported. The Fairness Doctrine was originally instituted in 1949 by the FCC and required broadcasters using the public airwaves to give equal time to opposing political views. The FCC repealed the measure in 1987 during Ronald Reagan’s presidency. Since talk radio is overwhelmingly dominated by conservative hosts, and liberal talk radio draws few listeners, the “equal time” provision would likely force many radio stations to pull popular conservative hosts from the air rather than air low-rated liberal hosts. A Barack Obama spokesman said recently that the president opposes reinstatement of the Fairness Doctrine. But a number of congressional Democrats have expressed support for the measure, including House Speaker Nancy Pelosi and Sens. Debbie Stabenow of Michigan and Tom Harkin of Iowa. DeMint said: "We need to make it a law that the FCC or this Congress cannot implement any aspect of the Fairness Doctrine."