The bill would give the Homeland Security Department regulatory authority over companies with computer systems crucial to the nation's economic and physical security. It would require that the companies take adequate precautions to safeguard their systems and would increase information-sharing about cyber threats between the private sector and the government.
The Democratic aides said they expect lawmakers to vote on an amendment on the floor that would require companies to notify consumers if their data is breached.
The auction proceeds would help to pay for extending unemployment benefits.
The spectrum legislation would authorize the Federal Communications Commission (FCC) to auction airwaves that currently belong to television broadcasters, splitting some of the revenue with the stations that choose to participate. The spectrum is potentially worth billions of dollars to wireless carriers, which are struggling to meet the growing data demands of smartphones and tablet computers.
Sen. Jay Rockefeller (D-W.Va.) said lawmakers "made great progress and are very close to a historic milestone" of including a nationwide broadband network for first-responders.
The FCC acted Wednesday to protect consumers from unwanted, automatic "robocalls" from telemarketers.
Democratic Reps. Henry Waxman (Calif.) and G.K. Butterfield (N.C.) wrote to Apple CEO Tim Cook on Wednesday, asking him for details after reports that the Path social networking app was downloading users' address books without their consent.
Sen. Chuck Grassley (R-Iowa) still plans to block President Obama's two FCC nominees despite the agency nixing LightSquared's high-speed wireless network on Tuesday night.
Sens. Dick Durbin (D-Ill.) and Tom Coburn (R-Okla.) demanded answers from Twitter CEO Dick Costolo on Wednesday about his company's new policy to allow governments to censor some tweets.
A White House spokeswoman said the administration is pleased with the "comprehensive approach" of the Senate's cybersecurity bill, which was introduced Tuesday.