Lobbyists already chafing under the Obama administration’s lobbying restrictions and congressional ethics rules could soon have a brand new headache: a nascent grass-roots movement that’s placed reining in lobbyists at its center.

Spearheaded by a coalition of campaign finance experts and activists called Represent.Us, the campaign is working to build grass-roots support for a measure that would drastically limit lobbyist fundraising, among other provisions. Dubbed the American Anti-Corruption Act, the plan would also curb unrestricted super PACs and make it harder for such groups to coordinate with candidates.

“It’s the boldest package of reform that we’ve seen maybe in a century that would change how Washington would work,” said Lawrence Lessig, a professor at Harvard Law School and founder of the anti-corruption group Rootstrikers. Lessig and other Represent.Us organizers say their goal is to build public pressure outside the Beltway before taking their plan to Capitol Hill.

“The view is that lobbyists should be requesting congressional action, but they should not then be fundraising, bundling and giving substantial sums to the people whose actions they are seeking,” said Trevor Potter, president and general counsel of the Campaign Legal Center and a key author of the proposal. The plan would ban members of Congress from raising funds from those who lobby them unless they recuse themselves from actions to benefit those donors.

In theory, K Street professionals might welcome a break from fundraising. The Represent.Us plan builds on a resolution approved by the American Bar Association last year that would impose a “cooling off” period on lobbyists making campaign donations, in addition to expanding lobbyist disclosure and registration rules. In June, the American League of Lobbyists also unanimously approved a package of changes aimed at expanding lobbying disclosure requirements.

But the Represent.Us plan received an instant thumbs-down from ALL, partly because one of the American Anti-Corruption Act’s key advisers was none other than Jack Abramoff, the former lobbyist convicted following the corruption scandal that led to sweeping new ethics and lobbying restrictions in 2007. Abramoff, who has since authored a book about his experience and set out to recast himself as an agent of change, remains anathema on K Street.

“I haven’t officially looked at it, but just knowing that Jack’s involved in it discounts it right from the very beginning,” incoming ALL President Monte Ward said. “A convicted felon who’s trying to pay off his debts is not somebody I would put a lot of credibility into.”

The league also considers the American Anti-Corruption Act’s lobbyist restrictions unconstitutional, outgoing ALL President Howard Marlowe said. Represent.Us organizers offer an extensive constitutional defense of the plan on their website, but Marlowe remains unconvinced.

Nevertheless, he said, lobbyists are receptive to rules changes and have voiced “serious concern” about the role of campaign contributions in the policymaking process. ALL spent 15 months coming up with its package of proposed changes, he noted, which were approved unanimously. The group debated different approaches to separating lobbying from fundraising but was unable to reach consensus on that point, Marlowe said.

“In the lobbying community, there are a number of lobbyists who believe that they cannot lobby outside of the campaign fundraising process,” Marlowe said. “The reason for that is that the easiest way to get the time and attention of a member of Congress and/or his legislative staff is at a campaign fundraiser.”

This is in part an unintended consequence of the post-Abramoff ethics overhaul, the Honest Leadership and Open Government Act, which banned lobbyist gifts and meals, said Marlowe.

ALL has toiled alongside the ABA and other change-minded groups to convince lawmakers to at least hold a hearing on expanding lobbying disclosure rules. The lobbying profession has grown to include armies of advocates who fall outside the Lobbying Disclosure Act, Marlowe maintains, because they engage in grass-roots or “grass-tops” advocacy, as opposed to meetings with lawmakers.

“They are seeing a lot of people who are coming before them who are paid to advocate but who are not registered,” Marlowe said. “And that does not do well for them, and it does not do well for us.”

But the group’s proposals to change lobbying rules have not yet generated much response on Capitol Hill, Marlowe said: “So far, the telephone hasn’t rung.”

Proponents of the American Anti-Corruption Act maintain it would change the culture of Washington more dramatically than either the Honest Leadership and Open Government Act or the other campaign finance proposals on the table, including disclosure and public financing legislation. The Anti-Corruption Act would also limit campaign donations from lobbyists and their clients to $500 a year and lengthen the cooling-off period for federal lawmakers leaving Capitol Hill for K Street.

If the plan’s authors were serious, “then they would sit down with us, and with the ABA, and with public interest groups” already working on lobbying fixes, Marlowe said. These players “don’t always agree by any means on everything,” he added, “but we definitely all agree on the need for transparency and accountability and the serious concern that we have about the role of money in the political process.”

Kate Ackley contributed to this report.