Mr. Emanuel formally announced his run Saturday to replace Mayor Richard M. Daley, who said in September that he wouldn’t seek a seventh term. State Sen. James Meeks, the pastor of a megachurch on the city’s South Side, was expected to officially join the race later Sunday.
Mr. Davis, a Democrat who has been in Congress since 1997, was tapped this month by a coalition of black leaders as its preferred candidate over other finalists, including Mr. Meeks and former U.S. Sen. Carol Moseley Braun.
Ms. Braun, the country’s first black female senator, has opened a campaign office and plans an official announcement soon.
The coalition, which included elected officials, business owners and activists, hoped to avoid splitting the black vote by uniting behind one candidate. Members said they chose Mr. Davis, who has served on the Cook County Board and the Chicago City Council, because of his broad government experience.