WASHINGTON — Speculation swirled over what appointments President-elect Barack Obama would make as he pivots from an election campaign to the task of building a Democratic administration.

Obama was set to receive the first of what will become regular briefings on highly classified information from top intelligence officials today. He has promised to hold a news conference later in the week as his transition team steps up its work.

Obama’s choice for chief of staff, Illinois Rep. Rahm Emanuel, appeared conflicted over whether to take on what promises to be a grueling job. Emanuel told Chicago’s WLS-TV that he was honored to be considered but needed to weigh the impact on his family. He was a political and policy aide in the Clinton White House.

“I have a lot to weigh: the basis of public service, which I’ve given my life to, a career choice. And most importantly, what I want to do as a parent,” Emanuel said in an interview aired Wednesday.

“And I know something about the White House. That, I assume, is one of the reasons that President-elect Obama would like me to serve. But I also know something about what it means to a family.”

In offering the post to Emanuel, Obama turned to a fellow Chicago politician with a far different style from his own, a man known for his bluntness as well as his single-minded determination.

After leaving the Clinton White House, Emanuel turned to investment banking, then won a Chicago-area House seat six years ago. In Congress, he moved quickly into the leadership. As chairman of the Democratic campaign committee in 2006, he played an instrumental role in restoring his party to power after 12 years in the minority.

Emanuel maintained neutrality during the long primary battle between Obama and Sen. Hillary Rodham Clinton, not surprising given his long-standing ties to the former first lady and his Illinois connections with Obama.

Several Democrats said Sen. John Kerry of Massachusetts, who won a new six-year term on Tuesday, was angling for secretary of state. They spoke on condition of anonymity, saying they were not authorized to discuss private conversations.

Kerry’s spokeswoman, Brigid O’Rourke, disputed the reports. “It’s not true. It’s ridiculous,” she said.

New Jersey Gov. Jon S. Corzine has downplayed reports that he was being considered for treasury secretary, telling New York radio station WCBS on Wednesday that he isn’t looking for the job and wants to stay in New Jersey.

Announcement of the transition team came in a written statement from the Obama camp.

The group is headed by John Podesta, who served as chief of staff under President Clinton; Pete Rouse, who has been Obama’s chief of staff in the Senate; and Valerie Jarrett, a friend of the president-elect and campaign adviser.

Several Democrats described a sprawling operation well under way. Officials had kept deliberations under wraps to avoid the appearance of overconfidence in the weeks leading to Tuesday’s election.