WASHINGTON (AP) _ The top contenders for the ``big three'' jobs in President Barack Obama's second-term Cabinet are all white men, rekindling concerns about diversity in his inner circle.

Now that Susan Rice has withdrawn under pressure from consideration as the next secretary of state, Democratic Sen. John Kerry of Massachusetts is the front-runner for the nation's top diplomatic post. Former Republican Sen. Chuck Hagel of Nebraska is Obama's favored candidate to run the Pentagon, and White House chief of staff Jack Lew is likely to be his next treasury secretary if he wants the job.

``The boys network is alive and well,'' Democratic activist Donna Brazile wrote on Twitter after Rice withdrew. ``The war on qualified women continues here in DC.''

Rice, the U.S. ambassador to the United Nations and a close friend of the president, dropped out of consideration for the State Department job Thursday. That followed months of withering criticism from Republicans over her initial comments about the attacks on Americans in Benghazi, Libya _ criticism several female House Democrats said smacked of sexism and racism. Rice is black.

Her withdrawal reignited questions about gender diversity in the upper echelons of the administration, a concern that has nagged at the Obama White House for years. The questions grew so persistent early in Obama's first term that the president invited his upper-level female staffers to a dinner to get their input on how to shake his administration's ``boys club'' reputation.

Now, senior administration officials are considering whether a prominent woman should be named to a top Cabinet post in order to create gender balance, according to a person familiar with White House thinking. That person spoke only on condition of anonymity because the person was not authorized to publicly discuss internal White House deliberations.

Among those whose names have been mentioned within the administration, former Defense Department official Michele Flournoy is being considered to lead the Pentagon and Lael Brainard, Treasury's undersecretary of international affairs, has been cited as a contender for her agency's top job. Former California Rep. Jane Harman has been discussed as a candidate for director of the Central Intelligence Agency.

A woman has never held the top job at any of those agencies.

White House press secretary Jay Carney said Friday, ``The president's approach has always been to seek excellence and as part of that believes diversity in terms of highly qualified candidates enhances excellence.''

Grumblings about gender diversity in the Obama administration have never focused on raw numbers but more on whether enough women were in high-powered decision-making roles.

``While numbers say a lot, they don't say everything,'' said Marcia Greenberg, co-president of the National Women's Law Center. ``Role and influence are important factors to bring to bear.''

Secretary of State Hillary Rodham Clinton certainly has had a high-powered role in the administration, as did Health and Human Services Secretary Kathleen Sebelius during the debate on health care reform. Longtime Obama confidante Valerie Jarrett serves as a White House senior adviser and has the strongest personal relationship with the president of anyone in the administration.

And women backed Obama over Republican Mitt Romney in the November election, 55 percent to 43 percent.

Yet a photograph released by the White House Friday showing Obama meeting with his senior advisers underscored where critics see problems. Jarrett is the only woman among the six aides in the room.

Obama appointed seven women to his 22-person Cabinet during his first term. An eighth woman, Rebecca Blank, is currently serving as interim Commerce Secretary after John Bryson resigned earlier this year.

Some women in the Cabinet are expected to stay on for at least some of the second term, including Sebelius and Homeland Security Secretary Janet Napolitano. Rice also will remain in the Cabinet as long as she stays in her post as the United Nations.

The controversy surrounding Rice centered on her assertion in Sunday talk shows that the attack in Libya was a spontaneous demonstration over an anti-Muslim video produced in the U.S. Rice later acknowledged that was wrong, but she also said she was relying on an account that was provided by intelligence officials, who have since said their understanding of the attack evolved as more information came to light.

Republican lawmakers, led by Sens. John McCain of Arizona and Lindsey Graham of South Carolina, aggressively criticized Rice for her statements on Benghazi, calling her unqualified and untrustworthy. MCain said she was ``not being very bright'' in her comments.

That comment in particular provoked the ire of a dozen House Democratic women, who leapt to Rice's defense and accused McCain and Graham of being motivated by sexism and racism. Rice never publicly agreed with their assessment.

In the aftermath of her withdrawal, other Democratic women lamented that they hadn't done more to assist Rice as the criticism mounted.

``The thing about Susan Rice that really bothers me, the women's groups, the civil rights groups, we should have stood up more,'' said Celinda Lake, a Democratic pollster, on MSNBC.

While Obama and others in the administration vigorously defended Rice, the White House never appointed a team to coordinate the administration's response to the criticism, in large part because Rice was not an official nominee.