WASHINGTON – Senators from both parties warned the National Football League on Thursday to get rid of a four-decade-old TV “blackout” rule or risk congressional action to restrict the league’s lucrative antitrust exemption, which allows NFL teams to negotiate radio and television broadcast rights together.

The blackout rule, which bars home games from being televised in a local market if they have not sold out, is unfair to fans who have helped the league reap billions of dollars in revenue from broadcast rights to games that are among the most-watched programs on TV, lawmakers said.

In return for their loyalty, “fans in the public are often treated like a fumbled football,” said Sen. Richard Blumenthal, D-Conn. “When places like Buffalo, New York, fail to sell out its 74,000-person stadium, the Bills game is blacked out for local fans.”

The Federal Communications Commission voted this fall to stop enforcing the NFL’s blackout policy, but the action did not end blackouts, which are written into the NFL’s private contracts with broadcast and cable companies.

Blumenthal and other lawmakers at a Senate Judiciary Committee hearing said the blackout rule has outlived its usefulness. The rule was adopted in the 1970s to encourage ticket sales at NFL games, which routinely sell out at stadiums across the country.

“The simple fact is that these rules only serve to benefit sports leagues and their member teams at the expense of the hardworking fans who support them so loyally through their money, time and passion,” said Sen. John McCain, R-Ariz.

During last year’s NFL playoffs, fans in Cincinnati, Indianapolis and Green Bay came close to experiencing blackouts when those games had not sold out just days before kick-off, McCain said. The blackouts were averted when local businesses bought tickets to bring the total above the NFL’s required threshold.

A bill co-sponsored by Blumenthal and McCain would revoked the league’s antitrust exemption unless it removes the blackout rule. The senators made it clear at the hearing that they would prefer not to enact a bill. Blumenthal and other lawmakers urged the NFL to act on its own.