WASHINGTON — Once again, President Barack Obama has been forced to abandon a friend and ally he wanted to nominate for a top job.
But this time, the resistance that pushed Lawrence Summers to withdraw from consideration for Federal Reserve chairman came from Obama's own Democratic base, not the conservatives who fought against him nominating Susan Rice as secretary of state. The opposition to Summers came at the end of a summer that also exposed other fissures between the White House and Democrats, many of whom are frustrated by revelations about the Obama administration's secret government spying programs and the president's support for military action in Syria.
"Most of the members of the Democratic caucus have a lot of respect and affection for the president but I do believe there is growing concern about his political judgment," Sen. Bernie Sanders, a Vermont independent who caucuses with the Democrats, said in an interview.
For Obama, any weakening of support within his own party could portend trouble to come for his second-term agenda. Because he already faces stiff resistance from Republicans to most of his policy proposals, the White House often needs to secure nearly every Democratic vote to pass Obama-backed legislation. And soon the president may come calling on Democrats to take tough votes during the fall fiscal fights, particularly if he makes concessions to Democrats on entitlement reform and spending cuts.
Summers, who is a Harvard University economist and former Obama adviser, informed the president on Sunday that he was withdrawing as a contender to replace current Fed chairman Ben Bernanke. The president has said he plans to nominate a new Fed chair this fall, before Bernanke's term ends in January.
With Summers' taking himself out of contention, current Fed vice chairwoman Janet Yellen has emerged as the front-runner.
The White House on Monday bristled at questions about the Democratic opposition to Summers. But the tumbling support for the 58-year-old was well known to Obama and his advisers before the economist formally withdrew.
When Summers emerged this summer as the likely choice for the Fed post, more than 20 Democratic senators signed a letter to Obama expressing support for Yellen. And some anti-Summers Democrats appealed to Obama in person during private meetings on Capitol Hill, leading the president to make a robust defense of his former adviser.
Union leaders, another key base of support for Obama on the left, also came out in support of Yellen, with AFL-CIO President Richard Trumka saying she understood that the role of Fed chair was not only to curb inflation but also to reduce unemployment.
Democrats spent much of August and September gauging support for Summers on the Senate Banking Committee, the panel that would have had to approve the economist before sending his nomination to the full Senate. By the end of last week, a Senate Democratic aide said it was clear there would be at least four Democratic no votes on the committee, including Jeff Merkley of Oregon, Elizabeth Warren of Massachusetts, Sherrod Brown of Ohio and Jon Tester of Montana.
A fifth Democrat was also trending away from Summers: Heidi Heitkamp of North Dakota.
The dearth of Democratic support meant the White House would need to rely on the committee's Republicans to get Summers approved. On Friday, Merkley called the Senate Democratic leadership to update them on how the vote totals were shaping up. He also called the White House and left a message for chief of staff Denis McDonough, according to the Senate aide, who was not authorized to publicly discuss the internal deliberations by name and spoke on condition of anonymity.
Summers pointedly noted that the political winds were blowing against him in a letter to Obama on Sunday formally withdrawing from consideration.
"I have reluctantly concluded that any possible confirmation process for me would be acrimonious and would not serve the interests of the Federal Reserve, the administration or, ultimately, the interests of the nation's ongoing economic recovery," he wrote.
The Democratic criticism of Summers focused on both his policies and his personality. Some lawmakers and economists criticized Summers for the role he played in deregulating parts of the financial industry during his tenure in the Clinton administration, while women's groups were critical of comments he had made about female aptitude in math and science.
Bill Burton, a former Obama White House official, defended the president's decision to consider Summers for the post despite the controversy that surrounded him. And he cast the pushback from Democrats, not only against the Summers nomination but also on other issues, as part of the political reality that faces presidents after winning re-election.
"Second term presidents often have more difficulty getting even simple things done," Burton said.
Summers' withdrawal marks the second time since Obama's re-election that he has lost his top choice for a high-profile job even before announcing an official nomination.
Rice, a close friend of the president, was a leading contender for secretary of state. But faced with blistering criticism from Republicans about her initial explanation of the deadly attack last year on Americans in Benghazi, Libya, Rice withdrew from consideration in December, saying she did not want her potential confirmation hearing to be a distraction for the president.
Obama later named Rice his national security adviser, a position that does not require Senate confirmation.
It's unlikely the president will find a similar fallback post for Summers, given that he's already served as Obama's top in-house economist.
Associated Press writers Donna Cassata, Sam Hananel and Jim Kuhnhenn contributed to this report.
Follow Julie Pace on Twitter at http://twitter.com/jpaceDC