Congress passed new legislation on Tuesday that would give the Federal Communications Commission the authority to auction off television companies' broadband spectrum, so it can be reallocated for mobile and internet companies.

Participation in the sale would be voluntary and broadcasters and cable companies would be paid for any spectrum that they allow the commission to put on the block.

However, the FCC's dreams of easing the spectrum crunch caused by the growing popularity of internet connected phones and tablets may die in the Democratic-controlled Senate.

Republicans in the House corralled the legislation into a Social Security payroll tax extension bill. Democrats have threatened to veto the bill in the Senate, because it includes provisions that weaken air pollution regulations and call for the construction of a pipeline from Canada to the Gulf of Mexico.

Though the prospects of passage are dicey, FCC chairman Julius Genachowski praised Congress. For more than a year, Genachowski has been working to find a plan that the television industry can embrace, while warning that inaction will slow the development of new technologies and imperil high-speed internet.

Incentive auction authority, which has broad bipartisan support, needs to become law, Genachowski said in a statement. Unless we free up new spectrum for mobile broadband, the looming spectrum crunch risks throttling our mobile economy and frustrating mobile consumers.

The bill was approved by a vote of 234-to-193, largely along party lines.