By David Nather, CQ Staff

Last summer, Barack Obama released a lengthy list of all the earmarks he had asked for in the fiscal 2008 spending bills. The Democratic presidential candidate had made open government one of his campaign themes, and he wanted to show he was true to his word.

There was just one problem: The Illinois senator had never produced the same kind of list for the earmarks he requested in his first two years in the Senate, despite numerous requests from the media. That gap in disclosure was bound to get more attention this week, given that he and his two presidential rivals had signed on to a measure pushing for a one-year halt to all earmarks.

So on Thursday, Obama reversed course. He released a list of all of his earmark requests for his first two years. And he immediately challenged his Democratic opponent, Sen. Hillary Rodham Clinton of New York, to disclose all of her requests, too.

The maneuvering was just the latest example of how the three top presidential contenders, all senators, have recognized the growing political potency of the debate over earmarks. John McCain of Arizona, the presumed Republican presidential nominee and a longtime critic of earmarks, has been stepping up his rhetoric. And Clinton and Obama have spent the week bending over backward to turn themselves into critics of the practice, even though both have been requesting earmarks for years.

“This is a recognition by the candidates that earmarks are a defining issue in this campaign,” said Thomas A. Schatz, president of Citizens Against Government Waste, a group that has been highly critical of the practice.

It’s the classic dilemma for senators who run for the White House: They have lengthy public records that can undermine any position they take on the campaign trail. And a vote on an uncomfortable issue can put those histories under a microscope, forcing them to backtrack in hopes of finding safer ground.

Sen. Jim DeMint , R-S.C., stepped up the pressure over earmarks this week by pushing an amendment to the fiscal 2009 budget resolution (S Con Res 70) calling for a one-year moratorium on all earmarks. The debate over the amendment was tailor­-made for McCain, who is making his fight against “pork” a central issue of his campaign.

But even liberal groups recognized the power of the amendment as a symbol of the Democratic candidates’ commitment to overhauling Washington — despite the opposition of their party’s leadership.

“I think it’s the beginning of a competition for who’s really going to clean out the stables, because that’s what this election is going to be about,” said Robert Borosage, co-director of the Campaign for America’s Future, a liberal advocacy group.

Clinton seemed to have the hardest time deciding her approach to the debate. Through a statement by spokesman Philippe Reines on Thursday, she insisted that she already publicizes the earmarks she receives — although Obama was pushing her to disclose her requests.

In addition, Clinton didn’t promise not to seek any earmarks this year, despite her support for the moratorium. Instead, she promised only to limit her requests to “the most critical needs for New York and America,” particularly health care and homeland security. Obama’s aides, by contrast, say he won’t ask for any earmarks this year, regardless of what happens with the DeMint amendment.

Histories Vary

McCain doesn’t have to stretch to convince voters he’s a critic of earmarks. He got none last year, and he says he has never asked for one — a claim that is mostly accepted by fiscal watchdog groups.

Both Clinton and Obama, however, have sought millions of dollars in earmarks for their states in the past. Last year, for example, Clinton ranked 10th in earmarking out of all senators, winning $342.4 million for New York through requests she made on her own and with other Senate colleagues, according to the fiscal watchdog group Taxpayers for Common Sense.

Obama’s total was well below the Senate average, but he still won $98.6 million in earmarks for Illinois on his own and with other lawmakers, according to the watchdog group’s figures.

Clinton has taken extra heat for cosponsoring a $1 million earmark for a museum celebrating the 1969 Woodstock music festival, but, for the most part, her earmarks and Obama’s have not been out of the ordinary. Clinton, for example, helped win $1.6 million last year for a mapping project for a defense health program at the New School University, according to Taxpayers for Common Sense. She secured the earmark with the help of New York colleague Charles Schumer, also a Democrat, with whom she has worked on most of her earmark requests.

Obama, meanwhile, won $345,000 for sewer improvements in northeast Illinois, among other projects.

Issuing a Challenge

Last weekend, McCain announced that he was cosponsoring DeMint’s earmark moratorium amendment and challenged Obama and Clinton to join him. They did so, perhaps largely to avoid suffering through months of McCain attacks.

“I doubt that, if they were not running for president, they would be even close to doing this,” said Schatz.

The Democrats’ move appeared to have the desired effect, with McCain offering grudging credit for their support.

“I am encouraged by some of my Democratic colleagues’ newfound enthusiasm for suspending this practice for a year. I hope their recent commitments do not wane once they step off the campaign trail,” McCain said in a statement Thursday.

Clinton and Obama may also have shielded themselves against attacks from each other on the issue of fiscal waste. “I think they’re both doing it to avoid criticism from each other,” said Peter Sepp, a spokesman for the National Taxpayers Union.

Nevertheless, those who support DeMint’s amendment aren’t about to reject Obama’s and Clinton’s help just because they’ve taken earmarks in the past.

“If all we could rely on was people who didn’t take any earmarks, we’d never win,” said Steve Ellis, vice president of Taxpayers for Common Sense.