Lightfoot — a firecracker Democrat who quickly brandished a national hate-hate relationship with conservatives — faces credible threats from at least three opponents in the nine-person race. Her unfavorable ratings have soared with Chicagoans fed up with gun violence. In recent polling, she has failed to break into the top two.

All that adds up to the stunning prospect that a sitting big-city mayor could be eliminated from re-election contention in the first round of voting.

"It's looking harder and harder for her," one of her competitors, Rep. Jesús "Chuy" Garcia, D-Ill., said in an interview. "It's a hell of a front to be fighting on, from her vantage point."