The Gang of Six lost its strong blocker on the right Tuesday, as Sen. Tom Coburn

pulled out of the bipartisan deficit reduction talks and predicted no meaningful deal can be reached until Democrats accept a greater share of savings from government benefit programs. 

"These guys have worked hard, and we had 80 percent of some significant things the country needs to do," the Oklahoma Republican told POLITICO. "But right now, I don't see us solving what needs to be solved." 

Coburn's departure adds to the pressure on the remaining five to show real progress this week, and Democrats took heart that Republican Sens. Saxby Chambliss of Georgia and Mike Crapo of Idaho are still active in the discussions, which will continue Wednesday. 

"At many points, we've hit rough spots; I hope this is just that," said Senate Budget Committee Chairman Kent Conrad (D-N.D.). Crapo's office used similar language expressing hope for a resolution. "The group is facing tough issues," the statement read. "But it has faced tough issues before and continued to work." 

But the loss is ominous, and Chambliss signaled that to make a deal work, Coburn would have to be brought back into the fold. 

"We'll continue to get together because there's still ideas," Chambliss said. "But there won't be a proposal by five of us. It's got to be six of us. 

"I want Tom Coburn [to be] a part of this. He's been with us 10 months on the debt commission and debate, now five months in this discussion, and he needs to be a part of it." 

One of the strongest political partners in the deficit reduction effort, Coburn is often the most mercurial as well, and Tuesday's departure followed several weeks of mood swings over the prospects for a deal - and tensions with Democrats over what Medicare savings can be achieved. 

Yet for all that, he avoided fanfare Tuesday after investing so much time in the effort. Arriving shortly before a 2:30 p.m. meeting of the six senators, Coburn came without staff and appeared to stay less than 10 minutes, walking past a single reporter outside without comment. 

"We're at an impasse. There's no reason to talk about the same things over and over and not getting any movement," he said later. "It's just a recognition that we can't get there." 

"I'm not planning on participating at this time. If things change, I will."

Chambliss, who arrived for Tuesday's meeting with Conrad and stayed after Coburn left, is distressed by the ups and downs of the talks. The Georgia Republican remains important because of his commitment to the effort and his friendship with Speaker John Boehner (R-Ohio). But if either Chambliss or Crapo were to pull out, it would be virtually impossible for the other to remain. That would erase in turn what many still see as the Senate's last, best chance of getting consensus on a broad-based deficit reduction plan to match the $4 trillion, 10-year target set last December by the presidential debt commission.

Absent agreement, the Senate Budget Committee remains at an impasse. The White House has belatedly recognized that it has a stake in reaching out to the few Republicans willing to go public in support of new revenues as part of the equation. 

Apart from its secrecy and a certain measure of what critics see as elitism, the Gang of Six's trademark has been a willingness to take on tough subjects such as taxes and major entitlement reforms, including Social Security. A major following has grown up in both parties, with nearly half the Senate turning out for an early morning meeting organized by Coburn last winter and joining a letter-writing campaign this spring in support of the effort. But the White House and leaders in both parties have nervously watched for fear of losing control over the debate. 

As the months passed, Republicans have become wary of tax increases. Alabama Sen. Jeff Sessions, the ranking Republican on the Budget Committee, has pressed hard on this point, and Coburn and the anti-tax activist Grover Norquist engaged in a high-profile debate on the revenue question. 

Last week, Senate Minority Leader Mitch McConnell (R-Ky.) stepped in to stress that the bipartisan Gang is no substitute for the leadership's House-Senate negotiations with the administration over what steps are needed before raising the debt ceiling. McConnell is sensitive to any suggestion that taxes be part of the solution, and he has much more control of the agenda in the White House talks, where he is represented by Senate Minority Whip Jon Kyl (R- Ariz.). 

Across the aisle, Durbin has remained active in the Gang of Six and acts as a bridge to the Democratic leadership. Coburn told POLITICO that the "impasse" he described over entitlement savings was chiefly between him and Durbin. 

The precise scope of what more savings he wants is not certain. But people familiar with the talks said Coburn has been pressing for as much as $130 billion in additional Medicare savings above the $400 billion recommended by the commission last December. And critics argue that this would reach a point of jeopardizing care for the elderly. 

"I don't want to get into the specifics, but there are some differences," Durbin said, when asked about the Medicare divide between himself and Coburn. "It shouldn't come as a big surprise that Tom and I would have a difference of opinion on some issues. We have managed to work out so many - scores of them - leading up to this point. I don't know if he can rejoin us; it would be great if he could."

Durbin said Coburn called him Tuesday morning to give him an advance warning of his dropping out. Durbin said he told Coburn he was "disappointed" but that "we'll continue to do our work."

A GOP bid to expand and hasten offshore oil drilling in the face of $4-a-gallon gasoline prices suffered an overwhelming defeat in the Senate on Wednesday, four days after President Barack Obama directed his administration to ramp up U.S. oil production.

Five Republicans joined 52 Democrats or independents in rejecting a bill written by Senate GOP leader Mitch McConnell to speed up decision-making on drilling permits and force previously scheduled lease sales in the Gulf of Mexico and off the Alaska and Virginia coasts. The Obama administration suspended several lease sales after last year's massive BP oil spill.

The bill was supported by 42 Republicans, well short of the 60 needed to advance it. Several GOP senators complained that the bill gave too much ground to the Obama administration, including a provision that would require independent reviews of oil companies' plans for responding to major oil spills before they could get drilling permits.

Sen. David Vitter, R-La., said McConnell's bill did not go far enough to expand drilling in the eastern Gulf of Mexico near Florida and off the Pacific coast. He said it also "increases the burdens and requirements and hurdles of even the new Obama regulations that have been put in place since the BP disaster."

Vitter and fellow Louisiana Sen. Mary Landrieu, a Democrat, also complained that the bill wouldn't direct royalties from offshore drilling to states where drilling occurs.

After the House passed similar legislation last week, Obama on Saturday directed the Interior Department to extend existing leases in the Gulf and off Alaska's coast and hold more frequent lease sales in a federal petroleum reserve in Alaska.

Both parties say that despite the BP spill, they want to allow responsible oil and gas drilling off the U.S. mainland and in Alaska. But they criticize each other's approach.

Democrats assailed the GOP bill as unnecessary and a giveaway to big oil companies, while Republicans said the measure would spur production that would reduce U.S. dependence on foreign oil and create thousands of jobs.

"Today's vote shows that `Drill Baby Drill' may be a catchy slogan, but it is not an energy policy," said Sen. Robert Menendez, D-N.J., who is opposed to drilling off the Atlantic coast.

McConnell called the bill a "modest approach" that takes concerns of both parties into account to achieve a practical result. "By unlocking our own domestic resources, and speeding up the permitting process, our plan would actually do something to increase supply, putting downward pressure on price" at the pump, the Kentucky Republican said.

White House spokesman Clark Stevens said the Senate bill was unnecessary, noting that the Obama administration has already taken many of the steps advocated in the bill, including a one-year extension of leases in the Gulf of Mexico and certain areas of Alaska.

What remained in the GOP bill "would have undercut the important safety standards put in place following the largest oil spill in U.S. history," Stevens said. "These are the very standards that are allowing the administration to expand drilling safely, and industry has clearly demonstrated that they can meet them."

The Interior Department has issued 53 shallow-water permits since late February, Stevens said, and approved permits at 14 deepwater wells.

Interior Secretary Ken Salazar said this week that Congress should change the law to allow leases onshore to be shorter than 10 years to pressure companies to drill sooner. Currently, 41 million acres of public lands are leased, but only 12 million acres are producing oil and natural gas, Salazar said.

Offshore, the Interior Department already has the ability to extend or shorten the length of a lease.