Former Sen. Carol Moseley Braun (D-Ill.) formally joined the Chicago mayor’s election race Saturday, according to press reports.

Moseley Braun is the first black woman in history to serve in the Senate. Elected in 1992, she represented Illinois for one term before losing her reelection bid to then-Sen. Peter Fitzgerald (R-Ill.). She later was confirmed as U.S. Ambassador to New Zealand and was a failed candidate for the 2004 Democratic presidential nomination.

Moseley Braun joins an already crowded field of candidates vying to be Chicago mayor since Richard Daley announced he was not running for a seventh term. Among others, Rep. Danny Davis (D-Ill.) and ex-White House chief of staff Rahm Emanuel are also running for the position.

Polling indicates that Emanuel is the front-runner in the race for now. In her announcement Saturday, Moseley Braun went after President Obama’s former chief of staff, also an ex-Illinois congressman, who is already running TV commercials..

“Mr. Emanuel, your commercials post a completely false choice,” Moseley Braun said during her announcement speech, according to The Chicago Tribune. “You may not understand it, but the challenge we face is not whether Chicago will be a second tier city, but whether our city will be great for all its citizens.”