As the lobbying battle over net neutrality is reaching a fever pitch, opponents are crying foul after a top staffer to Sen. Byron Dorgan (D-N.D.) announced her departure for Google.

The Internet search giant has been aggressively supporting enactment of net neutrality rules, which would prevent phone and cable companies from discriminating against some types of online content.

Frannie Wellings, Dorgan’s telecom adviser on the Senate Commerce, Science and Transportation Committee, has been the Senator’s primary staffer assigned to the issue. Dorgan, a longtime supporter of net neutrality legislation, authored the Senate’s version of the bill in 2007.

Google said it didn’t hire Wellings for her accessibility to Dorgan, but rather for her expertise on the issue. Wellings pushed for net neutrality at the Free Press, a nonprofit focused on making the Internet more accessible, before joining Dorgan’s staff more than two years ago.

“We’re hiring Frannie for her substance and knowledge of the consumer protection community,— Google spokeswoman Mistique Cano said. “Her primary role will be to lead Google’s work with trade associations, industry partners and advocacy groups.—

Wellings will be a federal policy outreach manager, a newly created position at the tech company. It’s unclear whether she will register to lobby since her primary role will be dealing with third-party groups.

Wellings will register “if she does end up doing lobbying activity,— Cano said.

Dorgan spokesman Justin Kitsch said Wellings notified Dorgan about her departure Tuesday.

“Her last day has not been set, but we expect it will be in the next four to six weeks,— Kitsch said in an e-mail. “Previously, when she told us she was in discussions about a potential new job, she was recused immediately from any issues where there could be a potential conflict of interest, including Network Neutrality.—

Despite Google’s attempts to carve out Wellings’ position as focused on downtown, Republican critics still argue that Wellings’ move to Google, when net neutrality is such a crucial issue, is disconcerting.

“It looks like the revolving door is alive and well, especially if you are with Free Press, Google and Dorgan’s office,— one Republican operative said.

Wellings is hardly the first senior staffer to exit for downtown.

Several former telecom staffers on both sides of the net neutrality issue have gone downtown to prominent positions, including Jot Carpenter, a former aide to then-Sen. Mike Oxley (R-Ohio) now at CTIA-the Wireless Association, and Brian Rice, a former communications policy adviser to Sen. John Kerry (D-Mass.) who is at Verizon.

Reform groups have unsuccessfully tried to push Congress to enact measures that would lengthen the cooling-off period for former staff and Members of Congress. Most recently, they pushed a measure that would have required senior staff, earning 75 percent or more of their bosses’ salary, to publicly disclose job negotiations as part of the Honest Leadership and Open Government Act of 2007.

Congress decided not to include that provision because it was deemed that ethics rules already addressed the issue, according to Public Citizen’s Craig Holman.

“Unfortunately all that information remains private and confidential,— Holman said.

Wellings’ departure comes as telecom, wireless and cable companies have mounted an aggressive offensive to thwart efforts at the Federal Communications Commission to implement net neutrality regulations.

“It’ll be the biggest issue for network providers going forward,— one Democratic telecom lobbyist said. “It’s No. 1, 2, 3, on the priority list.—

Republicans have been protesting newly installed FCC Chairman Julius Genachowski’s call to require Internet providers to deliver online content without discrimination. The proposed rules would prevent carriers from blocking content and technologies on their networks.

The net neutrality rules are part of a national broadband plan that is due to Congress in February.

House Minority Leader John Boehner (R-Ohio) and Minority Whip Eric Cantor (R-Va.) sent a letter to the White House and the FCC this week, arguing against the FCC’s move. Senate Republicans are working on a similar letter, according to a telecom lobbyist.

Google supporters discounted Wellings’ move as being a “game-changer— in the debate since Google and Dorgan are “on the same page,— according to one lobbyist.

Similarly, Maura Corbett, a partner at Qorvis Communications and a friend of Wellings, said, “This looks to me like opponents of net neutrality trying to have it both ways.—