WASHINGTON — Lawrence H. Summers' decision to bow out of contention for the Federal Reserve chairmanship represented a triumph for liberal Democrats, putting on powerful display their ability to pressure the White House in a way that could spell further complications for President Obama.
In just the last two weeks, liberal Democrats have joined with key Republicans to oppose his request for congressional authorization to launch a military strike against Syria as well as the prospective Summers nomination.
"There are many, many issues . . . where the president is moving in a direction which is very different from the people who voted for him want," said Senator Bernie Sanders, a Vermont independent. "And I feel very much that the president is becoming isolated and out of touch in the White House from the people who support him."
The diminished support from liberals could alter Obama's ability to negotiate with a divided Congress, as imminent deadlines approach for a government shutdown, as well as a default on the nation's debt.
It is far different than when Obama took office and could count on nearly unified party support for legislation such as health care and the stimulus bill. While he has clashed with conservatives since he first took office, he has seldom faced significant setbacks from within his own party.
Sanders, one of the most liberal senators, said several new members of the chamber, including Elizabeth Warren and Edward J. Markey, both Massachusetts Democrats, have helped build a larger liberal wing, which he vowed would become a counterbalance to the conservative Tea Party movement and more frequently challenge Obama from the left.
"A lot of progressives are thinking beyond Obama," said Adam Green, cofounder of Progressive Change Campaign Committee, a liberal advocacy group active in Warren's campaign. "If we can do it during his presidency, great. If he's intent on just playing defense, we'll lay the groundwork and pass big change in a couple of years."
Obama has been at odds on several issues with the left. Revelations about the National Security Agency's aggressive surveillance programs caused angst among those concerned about privacy. Warren and Markey were among a group opposing the president's compromise with Republicans on college loan rates. Democrats largely abandoned Obama on authorizing military action against Syria; no members of Massachusetts' all-Democratic delegation said they would vote in favor of strikes.
On Sunday, when Summers withdrew from consideration, it underscored the left's ability to organize and disrupt the plans of the Democratic Party's standard bearer. Obama for months had been leaning toward picking the former Harvard University president even amid complaints about his role in deregulating financial markets and questions about his demeanor.
The White House faced an uphill battle in getting Summers confirmed by the Senate Banking Committee, much less the full Senate. Several Democratic senators, including Sherrod Brown of Ohio, Jeffrey Merkley of Oregon, and Jon Tester of Montana, planned to oppose Summers in committee.
Warren was also expected to oppose him, although she did not say so publicly.
In an interview Monday, Warren said she spoke with Summers within the past two months, sometime after she signed a letter backing Summers's chief rival, Janet Yellen, for Fed chief. But the matter did not come up, she said. "We had a good wonky conversation about the economy, regulations, data," Warren said. "We talked about economic policy."
"We've talked off and on for years," added Warren, who has known Summers since before she came to Harvard and had several encounters with him when the two worked for Obama.
Summers declined requests for comment. Warren said she had numerous "back and forth" conversations with both Obama and other White House officials, "just make sure they know my views."
"It's powerfully important to have the right chairman of the Federal Reserve," she said, adding that "The president is doing the right thing to think it through and talk to the right people."
Warren did not respond directly to questions about the left's desire to flex its muscle or remind Obama not to take liberals for granted. "The president is great," she said.
On Monday, Obama sought to recenter the focus on the economy. He began a weeklong push on the issue, spending the day marking the fifth anniversary of the US financial crisis.
While not addressing rifts within his own party, Obama lashed out at the GOP's own faction: conservative Republicans. He said they were wasting time trying to repeal his signature health care law ("It was an issue in last year's election, and the candidate who called for repeal lost.") And he reiterated he would not negotiate over whether to raise the debt ceiling, a maneuver that would allow the federal government to borrow more money to pay for spending that has been authorized.
"Let's stop the threats, stop the political posturing," Obama said, adding, "I cannot remember a time when one faction of one party promises economic chaos when it doesn't get everything it wants."
House Speaker John Boehner, who has spent much of the past two years trying to patch rifts within his own party, took offense at the president's words. "It's a shame that the president could not manage to rise above partisanship today," Boehner said in a statement. "Instead, he should be working in a bipartisan way to address America's spending problem — the way presidents of both parties have done before."
Representative James P. McGovern, a Worcester Democrat and one of the most liberal members of the House, said liberals have been more willing to bend than conservatives. But there are issues on which they will not compromise, including military strikes, which may have caught the president off guard. The same goes for Social Security, food stamps, and other segments of the budget that have been threatened, he said.
Obama now finds himself in a political predicament that has some similarities to what President Clinton faced when Democrats were upset with him over his budget plans and his welfare reforms. He ended up working with moderates and with Republicans to push some of his priorities through, always seeking what his White House deemed "the vital center."
Obama, though, faces a Republican Party that is unlikely to cut any deals with him, and in a Congress that is increasingly polarized, with little center ground to seek.
"I think it's too hard and too late," Chris Lehane, a former Clinton adviser, said of whether Obama could pull off the same strategy as Clinton did in the 1990s.
Lehane said that while Obama has "a year or so left to get something done domestically," the current political situation might require a new approach. "It's thinking about what you as president can do that doesn't necessarily require Congress," he said.