Marty Paone, who worked on behalf of two backers of the Keystone XL pipeline, received the Obama administration’s fourth special waiver exempting him from an executive order meant to limit lobbyists “revolving” into government jobs. (Andrew Cullen/Reuters)

In the three months since Marty Paone took on the job as President Obama’s chief liaison to the U.S. Senate, he has helped plot strategy on the confirmations of top administration appointees, a partisan showdown over funding the Department of Homeland Security and the president’s request for the authorization for use of military force.

What he more pointedly did not work on was the very first piece of legislation the new Congress considered this year: a contentious bill to authorize construction of the Keystone XL pipeline. Just before his arrival in the West Wing, Paone served as executive vice president for the Prime Policy Group, where he lobbied on behalf of two of the project’s major proponents, the American Petroleum Institute and the In Situ Oil Sands Alliance.

His lobbyist past meant Paone needed a special waiver to work at the White House — the fourth the administration has granted since Obama signed an ethics executive order on his second day in office.

At the time, Obama said he was taking aim at the influence-peddling apparatus endemic to the culture of official Washington, pledging to close “the revolving door that lets lobbyists come into government freely and lets them use their time in public service as a way to promote their own interests . . . when they leave.”

The Paone hire may be the starkest example of both the success and the failure of the president’s initiative, which the administration credits with reducing special-interest influence on the government and bringing new, and more diverse, faces into the executive workforce.

Former White House senior counselor John D. Podesta, founder of liberal think tank Center for American Progress, is among the advocates who worked for the Obama administration who were not technically lobbyists. (Manuel Balce Ceneta/AP)

Critics deride it as political grandstanding, a move that has deprived the administration of talent and has been repeatedly circumvented.

Even Stanford University political science professor Bruce Cain, who supports the order, said in an interview: “The problem that you have is that the political actors strategically adapt to the rules that you have. You have to realize you’re never going to completely close that influence gap.”

Some lobbyists — who under federal law are required to register only if they spend at least 20 percent of their time lobbying — chose to deregister once the rules took effect. The number of registrations dropped from 13,367 when Obama took office to 11,509 last year, according to an analysis by American University government professor James Thurber.

Jan Baran, a partner at the law firm Wiley Rein specializing in ethics law, said several people among his client base changed their lobbying statuses in response to the White House policy. “After the executive order, there was a wave of examinations of ‘Gee, do I really need to be a registered lobbyist under the law?’ ” Baran said.

White House spokesman Eric Schultz said the rules have had a major effect on how government functions. The measure prohibits those who have been registered lobbyists in the past two years from working at an agency they had lobbied, or on an issue they had worked on, and bars appointees from accepting gifts from registered lobbyists or lobbying groups while serving in government. It also prohibits administration appointees who later register from lobbying other executive branch officials or senior appointees for the remainder of Obama’s time in office.

“Our goal has been to reduce the influence of special interests in Washington — which we’ve done more than any administration in history,” Schultz said in a statement.

Former White House counsel Robert Bauer — who helped draft the order and implement it while in office — said that while some have questioned the move to deregister, the policy “had to be built practically as much as possible on settled definitions.”

“The law defined the term ‘lobbyist,’ and it made sense to start there,” Bauer said. “If there is unhappiness with this, then the answer would be, change the law.”

Some things have clearly changed. Although the administration has come under fire for its handling of the attack on U.S. facilities in Benghazi, Libya, the Internal Revenue Service’s probe of conservative nonprofits and Department of Veterans Affairs medical services, it has not experienced the type of conflict-of-interest scandals the past two White Houses experienced. And in an era in which the Justice Department is investigating former congressman Aaron Schock (R-Ill.) over questionable finances and Sen. Robert Menendez (D-N.J.) is expected to face federal corruption charges, the White House has escaped such pitfalls.

Under George W. Bush’s Interior Department, both Deputy Secretary J. Steven Griles and David H. Safavian, a former top aide at the General Services Administration and White House, pleaded guilty to felonies stemming from their relationships with convicted lobbyist Jack Abramoff. Two of President Bill Clinton’s Cabinet members — Housing and Urban Development Secretary Henry A. Cisneros and Agriculture Secretary Mike Espy — stepped down after becoming the targets of special-counsel probes, though Espy was later acquitted of accepting $35,000 in illegal gifts from businesses and lobbyists.

Jim Messina, who served as Obama’s deputy chief of staff during the first term, said the lobbyist restrictions meant “a younger, more diverse group of people who have risen to leadership. That will be a fundamental part of his legacy.”

Still, the rule has not blocked advocates from entering the administration — even if they’re not technically lobbyists. Deputy U.S. Trade Representative Robert Holleyman, who joined a year ago, promoted firms including Oracle and Microsoft as the head of the software trade association BSA from 1990 to 2013. BSA’s current president, Victoria Espinel, took that post after serving as Obama’s intellectual-property enforcement coordinator at the trade office. Before joining the administration, Jim Hock — who now serves as Commerce Secretary Penny Pritzker’s chief of staff — had founded 463 Communications, a communications agency for technology and clean-energy firms.

The liberal think tank Center for American Progress — which former White House senior counselor John D. Podesta founded and helped lead before joining the administration to oversee its climate and public lands agenda — had accepted major donations from environmentally minded billionaires Tom Steyer and Hansjorg Wyss before he joined Obama’s staff.

Some lobbyists deregistered before accepting senior administration posts, including Vice President Biden’s chief of staff, Steve Ricchetti, Cabinet Secretary Broderick Johnson and Tom Malinowski, assistant secretary of state for democracy, human rights and labor. Malinowski had initially been denied the chance to serve because he had lobbied for Human Rights Watch for more than a decade, but he joined in 2013 after his cooling-off period had expired.

More than 70 Obama appointees had served as lobbyists at some point in their careers, and many returned to advocacy after leaving. And at least a dozen former Obama aides have taken lucrative jobs in the high-tech and sharing economy sectors since leaving office, including former White House press secretary Jay Carney at Amazon.com and senior adviser David Plouffe at Uber.

But the White House has been loath to issue waivers for individuals who have lobbied within the past two years, even when it meant disqualifying strong candidates.

One former senior administration official said efforts to waive the rules “run into enormous difficulties” because of the public outcry that inevitably follows, such as when then-Defense Secretary Robert M. Gates recruited former Raytheon lobbyist William J. Lynn III to serve as his deputy. Ideally, an administration would have “more flexibility” to issue waivers, said the official, who asked for anonymity in order to discuss personnel matters.

James Hickey, president of the Association of Government Relations Professionals, questioned why the administration would bar some of Washington’s most experienced professionals from serving in senior positions.

“Way back when the Oklahoma gold rush took off, there were a lot of people who realized they needed trail guides to the Rockies. A lot of those who didn’t use trail guides . . . expired in the Rockies,” he said. “To a certain extent, the government relations professionals are trail guides.”

The unanswered question is whether Obama’s successor — regardless of party — will adopt a similar executive order, since it will expire once he leaves office.

Public Citizen government-affairs lobbyist Craig Holman said he “would love to see this ethics order put into statute, because if we don’t, whoever is going to be elected next is immediately going to throw this ethics order out the window.”

Hillary Rodham Clinton, who is considered the Democratic front-runner in 2016, did not make the same anti-lobbying pledge as Obama did when they were both running in 2008. But a spokesman noted she backed the 2007 lobbying reform law that then-Sen. Obama helped usher into law and had put forth an “open government” plan of her own.

Dan Meyer, president of the Duberstein Group, said he thinks it’s “unlikely” a Republican would adopt a similar ban, but he added: “It’s all up to one individual. . . . I think the track record has not only proven you’re denying yourself the chance to hire some good people, but the reform was phony.”

Vin Weber, a senior Republican strategist and lobbyist who regularly advises presidential candidates, had to quit a Pentagon advisory board as a result of the policy’s prohibition on lobbyists serving on federal commissions and advisory panels, though the administration jettisoned that provision last year after losing a case in federal appeals court.

Still, he said in an interview, “if I were asked by a presidential campaign, I’m not at all sure I would tell them to reverse the executive order. Not because the rule’s good, but because it’s an enormously politically difficult thing to explain.”

“Any administration now is going to have to implement a similar policy or explain why it won’t, or explain what changes they will make,” Bauer said. “It puts on the table an issue that every administration has to grapple with.”