Legislation to codify unfettered broadband access for content providers, a principle known as “net neutrality,” will soon be introduced in the Senate.

An aide to Sen. Byron L. Dorgan said the North Dakota Democrat will reintroduce his “Preserving Internet Freedom” bill, which he last sponsored in 2007. Maine Republican Olympia J. Snowe is expected to cosponsor the bill, as she has in the past.

Dorgan’s aide said the bill is intended to support and help codify new net neutrality principles announced Sept. 21 by the Federal Communications Commission (FCC).

“We’re trying to work through what it would look like,” the aide said, adding that the goal is to produce a bill that will “help [FCC] legislatively.”

The House is proceeding along a similar tack. Rep. Edward J. Markey , D-Mass., has introduced a bill intended to “complement” the FCC’s new mandates and ensure that they endure beyond the Obama administration.

Net neutrality is the policy of preventing broadband service providers from blocking certain traffic or establishing tiered pathways for Internet content. Supporters say it would level the playing field for content providers. Opponents, including Internet service and high-speed cable outfits, say it would chill online innovation.

The FCC’s proposed mandates would prohibit Internet service providers from selectively blocking or slowing content and applications.

These prohibitions also would apply to wireless providers for the first time, sending cadres of lobbyists from the big wireless companies up to the Hill to plead their case, spearheaded by their trade group, CTIA.

Applying net neutrality to wireless carriers means they could not block voice calling services, such as Skype or Google Voice on Apple’s iPhone.