His only other rival for the job, U.N. Ambassador Susan Rice, faced harsh criticism from congressional Republicans for her initial accounting of the consulate attack. Obama vigorously defended Rice, a close friend and longtime adviser, but GOP senators dug in, threatening to hold up her nomination if the president tapped her for the post.
Rice withdrew her name from consideration last week, making Kerry all but certain to become the nominee. People familiar with the White House's decision-making said support within the administration was moving toward Kerry even before Rice pulled out.
The son of a diplomat, Kerry was first elected to the Senate in 1984. He is also a decorated Vietnam veteran who was critical of the war effort when he returned to the U.S. He ran for president in 2004, losing a close race to incumbent Republican President George W. Bush.
Obama and Kerry have developed close ties in recent years. It was Kerry, during his 2004 presidential run, who tapped Obama as the party's convention keynote speaker, a role that thrust the little-known Illinois politician into national prominence.
Kerry served on Obama's debate preparation team during the 2012 election, playing Republican challenger Mitt Romney in mock debates.
"Nothing brings two people closer together than two weeks of debate prep," Obama joked on Friday. "John, I'm looking forward to working with you rather than debating you."
Kerry is Obama's first Cabinet appointee following the November election. The president is also mulling replacements for retiring Defense Secretary Leon Panetta and former CIA director David Petraeus, who resigned last month after admitting to an affair with his biographer.
Former Republican Sen. Chuck Hagel of Nebraska is a front-runner for the Pentagon post, but has been dogged by questions about his support for Israel and where he stands on gay rights, with critics calling on him to repudiate a comment in 1998 that a former ambassadorial nominee was "openly, aggressively gay."
Hagel apologized for that comment Friday.
Former Pentagon official Michele Flournoy and current Deputy Defense Secretary Ashton Carter are also under consideration to replace Panetta. Obama is also considering promoting acting CIA Director Michael Morell or naming White House counterterrorism adviser John Brennan as the nation's spy chief.
Associated Press writers Donna Cassata in Washington and Steve LeBlanc in Boston contributed to this report.
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