WASHINGTON – It was one of the few issues on which President Barack Obama and Vice President Joe Biden disagreed: how far to go in limiting the influence of lobbyists in government.

Biden privately complained that his boss' effort to slam shut the revolving door between K Street and the administration would deprive it of experienced talent, and he bristled when Obama's aides tried to block him from hiring a well-connected Washington operator who had lobbied for pharmaceutical and insurance companies, credit agencies and others.

Eight years later, that same confidant, Steve Ricchetti, is helping to run Biden's presidential campaign. Also involved to varying degrees are other advisers, operatives, fundraisers and allies with deep connections to Washington's lucrative lobbying, communications and strategic consulting industry.

That puts Biden at odds with powerful elements of his party's liberal base. Increasingly, they are expressing concern that the military contractors, Wall Street banks and other major corporations that paid members of Biden's inner circle while they were out of government could hold disproportionate power in a Biden administration.

Politically, it could limit Biden's ability to cast himself as the antidote to the anything-goes access peddling that has proliferated in President Donald Trump's administration. Under Trump, lobbyists and campaign donors have not only enjoyed access to the administration's highest levels but also have been tapped to lead Cabinet departments and have exerted remarkable influence over policies of intense interest to their former employers.

"It's worrisome, broadly speaking, that a Biden administration could end up abiding by the unfortunate bipartisan norms of putting people in posts where they oversee industries or employers they just left," said David Segal, co-founder of the group Demand Progress.

His organization was among those that sent a letter to the Biden and Trump campaigns this past week asking them not to appoint anyone to senior administration positions overseeing interests they served in the private sector. The letter called out Trump's administration for taking that dynamic "to new extremes," but Segal added that Biden's orbit includes "some folks with troubling track records."

Biden has pledged to "expand on and codify" the Obama administration's lobbying executive order — the same policy he had privately complained about. That plan would bar lobbyists from going to work for agencies they had tried to influence within the previous two years and bar departing officials from lobbying until the end of the administration.

With scrutiny intensifying, some Biden allies are now distancing themselves from their corporate work to better position themselves for official roles with the campaign, transition team or in a potential Biden administration.

Andrew Bates, a spokesman for Biden's campaign, said the former vice president's ethics proposal would be "the most ambitious" of "any administration in American history."

Bates said Biden is "deeply proud" of the ethics policies enacted in the Obama administration and of his work in the Senate before that "to curtail the influence of lobbyists, money and special interests in government."

But after eight years as vice president and decades in the Senate, Biden maintains extensive ties to Washington's permanent political class of policy and political experts who move between government and private-sector positions.

Ricchetti spent years as a registered lobbyist and through a company called Ricchetti Consulting Group is being paid by both the Biden campaign and AT&T, his only corporate client over the past nine years. Biden strategist Anita Dunn was also still doing work for AT&T in July.

As of Saturday, Dunn has taken "an official leave" from her firm, which had been paid millions in recent years to help an airline advocacy group, while also providing communications advice to an Israeli spyware firm and fugitive Nissan executive Carlos Ghosn, for whom the firm had been registered to lobby. It ended all those relationships in the past year.

A leading candidate to become defense secretary, Michèle Flournoy, started a firm whose website lists work for financial services, technology and pharmaceutical companies. Former CIA and Obama national security official Avril Haines, who consulted for the data-mining company Palantir, on Saturday resigned from Flournoy's firm to begin work for Biden.

None of these advisers are registered as lobbyists, reflecting a trend in which major corporate and foreign players hire former officials as consultants or as legal counsel, allowing them to use their connections and expertise while avoiding the notoriety and disclosure requirements that come with formal lobbying. This phenomenon was exacerbated by Obama's lobbying policy

Biden's more liberal challengers for the nomination, Sens. Bernie Sanders and Elizabeth Warren, both campaigned against K Street, in part to differentiate themselves from the candidate they now support.

Warren proposed a plan to expand the definition of lobbying to include consultants and lawyers who try to influence government, while barring corporate lobbyists from joining the government for six years. Supporters of Sanders and Warren are pushing Biden's team to go further than he has on those issues.

Jake Sullivan, who has been helping to develop Biden's policy positions and moderating virtual fundraising events, resigned this year from a job at the consulting firm Macro Advisory Partners, where he worked with the ride-hailing company Uber to try to preempt an effort in California to classify the company's drivers as full-time employees.

On Saturday, Antony Blinken, an Obama deputy secretary of state, who is running Biden's foreign policy operation, joined the campaign full time and took an unpaid leave of absence from his role as a managing partner in WestExec Advisors, a firm he co-founded with Flournoy.

Aaron Keyak, who was named director of Jewish engagement for Biden's campaign last month, took a leave from his public affairs firm, Bluelight Strategies.

Early in the Trump administration, the firm had been paid $10,000 a month for Keyak's help waging a public affairs campaign against the Gulf state of Qatar by Elliott Broidy, a Republican donor who owns a defense consulting firm. Federal investigators have since looked into whether that campaign violated foreign lobbying laws, but Keyak has not been interviewed by prosecutors, the Biden campaign said.

Some Democrats argue a Biden administration would be wise not to wall itself off from people with both government and private-sector experience.

"We can't all go to think tanks or into academia, and you wouldn't want to fill the government entirely with people who came from ivory tower institutions that are detached from the mechanics of Washington," said James Rubin, who had served as a foreign policy adviser to Biden in the Senate and then moved to the State Department in the 1990s before becoming a registered lobbyist.

In an effort to ease potential hurdles to joining a Biden administration, Rubin in recent weeks terminated his lobbying registrations for a range of clients.