President Obama formally nominated Sen. John Kerry, D-Mass., as his next secretary of state, avoiding a contentious confirmation battle over the nation’s top diplomat at a time when he can ill afford political drama.

“In a sense, John’s entire life has prepared him for this role,” Obama said of the Vietnam War veteran and foreign policy wonk of the Senate. “He’s not going to need a lot of on-the-job training.”

Such Cabinet assignments are usually marquee events, but the selection of Kerry comes amid raging debates over the so-called fiscal cliff and response to the deadly massacre in Newtown, Conn.

It was Kerry who gave Obama the keynote address during the Democratic National Convention in 2004, launching an Illinois state senator from obscurity into the political limelight. And Kerry also served as Obama’s debate partner in recent months, playing the role of Republican presidential candidate Mitt Romney.

The selection of Kerry means Massachusetts will hold a special election next year to fill the vacant Senate seat. Outgoing Sen. Scott Brown, R-Mass., could run again after losing his seat to Elizabeth Warren this year.

Kerry emerged as the frontrunner for the post after UN Ambassador Susan Rice pulled the plug on a potential bid. Rice’s description of the administration’s response to the terrorist attacks on the U.S. Consulate in Benghazi, Libya muddied the prospects of her confirmation.

Unlike Rice, Kerry is expected to breeze through confirmation, due in part to his lengthy stint in the upper chamber.

“John’s played a central role in every major foreign policy debate for nearly 30 years,” Obama said of his chosen successor to Secretary of State Hillary Clinton.

Obama had wanted to also roll out his pick for secretary of defense on Friday, but frontrunner, Chuck Hagel, the former Republican senator from Nebraska, has drawn criticism from Republicans and Democrats alike for his views on Israel and the LGBT community. Administration officials say Obama has not yet decided who will lead the Pentagon in his second term.