The Federal Election Commission meets on April 25 and hears Craig Engle, lower right, discuss a point about contributions from same sex married couples and single or joint checking accounts. (Bill O'Leary/The Washington Post)

President Obama’s once-broad ambitions to clamp down on the influence of special interests have been largely abandoned since his reelection, dismaying longtime allies in the campaign-finance reform movement.

The predicament will be on full display Tuesday, when all five members of the Federal Election Commission will be serving past the formal expiration of their terms. The panel’s sixth seat remains vacant. The president has not made a nomination to the FEC, which enforces the nation’s campaign finance laws, in more than three years.

For those who favor tougher regulation of money in politics, this follows a string of disappointments, including Obama’s decision this year to transform his campaign committee into an advocacy group, Organizing for Action, that can collect unlimited donations.

Obama also promised during his reelection campaign to pursue a constitutional amendment overturning Citizens United v. FEC, the 2010 Supreme Court opinion that allowed corporations to spend unlimited money on politics. Nothing has happened since.

In addition, the White House has not filled a position overseeing ethics and lobbying issues for more than two years — a job Obama created with great fanfare when he took office in 2009.

Reformers of both parties describe the president’s campaign finance record in unsparing terms.

“It’s disgraceful, absolutely disgraceful,” said Sen. John McCain (R-Ariz.), who ran against Obama in 2008 and has spent years trying to limit the amount of money that pours into federal political campaigns.

In a joint letter to Obama on Monday, seven reform groups expressed their “deep concern about the nation’s corrupt campaign finance system and about your failure, to date, as president to provide meaningful leadership or take effective action to solve this fundamental problem facing our democracy.”

White House spokesman Eric Schultz said in a statement that Obama “has taken historic steps to reduce the corrosive influence of money in politics.”

“President Obama has done more in the past four years to close the revolving door of special-interest influence than any president before him,” Schultz said.

When it comes to affecting the flow of private money into federal elections, however, many advocates think Obama has done more to open the spigot than close it.

In 2008, he became the first presidential nominee since Richard M. Nixon to reject public financing in his primary and general-election campaigns. He also shattered fundraising records during his 2012 reelection bid and allowed corporations to help underwrite his second inauguration with more than $8 million in donations.

But for many former allies, Obama’s decision to convert his campaign operation into a political advocacy group with unlimited funding was the final straw.

“The president has engaged in uncharted waters that open the door to influence,” said Democracy 21 President Fred Wertheimer, a longtime activist who describes Organizing for Action as “a precedent that other federal officeholders are likely to follow.”

Spokeswoman Katie Hogan said that contributions to OFA averaged $44 in the first quarter of 2013. She said the group “voluntarily discloses above and beyond what is required of issue advocacy groups despite most other [nonprofits] continually hiding where their funding comes from.”

For much of his political career, Obama has railed against the influence of big money in politics and has at times pushed for restrictions. On his first day in office in 2009, he signed an executive order restricting the ability of lobbyists to serve in the administration and barring appointees from lobbying for two years after they left office.

During his 2010 State of the Union address, Obama challenged the Citizens United decision, saying it “reversed a century of law that, I believe, will open the floodgates for special interests, including foreign corporations, to spend without limit in our elections.” The comment prompted Justice Samuel A. Alito Jr., sitting in the audience, to mutter, “Not true.”

The president also appointed a law school classmate, Norman Eisen, as special counsel for ethics and government reform, and posted visitor logs, daily public schedules, staff salaries and ethics waivers on the White House Web site.

But the ethics position has been vacant since 2010, when Obama named Eisen ambassador to the Czech Republic. White House aides say the job has been divvied up among other administration officials.

Several election law experts say it’s understandable that Obama has not pushed harder to overhaul the nation’s campaign finance system, given the state of political polarization and the Citizens United decision.

Columbia Law School professor Nathaniel Persily said it was hard to envision how Obama could persuade congressional Republicans to adopt any changes to the system because it “affects congressmen’s jobs, and it’s something they think they’re experts at.”

“Reforms are seen as a zero-sum game between the parties,” Persily said. “Any time or effort spent on campaign finance is time and effort not being spent on the budget, North Korea and/or immigration, all of which have a better chance of having a legislative solution.”

Voters are not clamoring for reform, either: The issue ranked 21st out of 22 issues in a January Pew Research Center poll when respondents were asked to name their top priorities for Obama and Congress, edging out global warming. Just 24 percent of respondents in a Washington Post-Pew Research Center poll last year thought more outside spending was having a negative impact on the election.

At the FEC, most commissioners are appointed by the Senate to six-year terms but are allowed to continue serving past that time until a replacement is found. Obama has put forward only one FEC nominee, labor lawyer John J. Sullivan, whose name was withdrawn after he came under fire for positions he took while representing unions.

Regardless of the appointment issues, the FEC has been racked by partisan dysfunction for years, frequently deadlocking 3 to 3 on major rulings.

The vacancy issue came up at last Thursday’s regular FEC meeting, which featured nearly two dozen schoolchildren in the audience for Take Our Children to Work Day. The scene prompted FEC Chairman Ellen Weintraub — whose term officially expired in 2009 — to pose a question.

“Anyone want to be commissioner?” she asked. A few kids raised their hands. “Write the president and tell him you want to be a commissioner, because we need somebody.”

Capital Insight survey research analyst Scott Clement contributed to this report.

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