CHICAGO (CBS) – Sparks flew between Rahm Emanuel and his two closest challengers at a mayoral debate Thursday night, but a new poll shows Emanuel continuing to add to his already sizable lead.

As CBS 2’s Susanna Song reports, the new Chicago Tribune poll shows Emanuel has 49 percent of the potential vote – just one percentage point short of averting a runoff in April. Gery Chico comes in second with 19 percent, followed by Carol Moseley Braun with 10 percent and Miguel Del Valle with 8 percent.

Braun, who was elected to the U.S. Senate in 1992 and has not won an election since that time, dropped from third place from second in prior polls. The Tribune says her support dropped after a debate at the Trinity United Church of Christ, in which she yelled that challenger Patricia Van Pelt-Watkins had been “strung out on crack.”

LISTEN: Newsradio 780’s David Roe reports

But it was Emanuel who was the target of criticism at the hour-long debate at Kennedy-King College Thursday night, which was sponsored by the Chicago Urban League and televised on WFLD-Fox 32. The debate careened from topic to topic with questions about public safety, education and business development.

With regard to public safety, Chico, the former Chicago Board of Education president, said while he was scared for his children who travel back and forth to school in the city. But he said Emanuel wouldn’t understand because he went to high school in the North Shore.

“Growing up like I did in our city like I did in the Back of the Yards, and living with the threat of violence – even in my own neighborhood – stays with you,” Chico said. “There are people like Mr. Emanuel who grew up on the wealthy North Shore, who probably never experienced that, and I think it makes it harder, harder to come to grips with what a plan would be to combat this.”

Braun also fired shots at Emanuel for not supporting the efforts of the Congressional Black Caucus, and accused him of hiding behind President Barack Obama to help him in the black community.

Miguel Del Valle shared how if elected, he’d find a way to help entrepreneurs start small neighborhood businesses.

“We need to bring those banks to the table, and we need to use the authority of mayor’s office to say that we need capital,” he said.

Braun and Emanuel explained how they would improve Chicago Public Schools.

“What I believe we should do, is we should have a collaboration of the teachers who are in there on the front lines, if you will, because those teachers are not there to make a gazillion dollars. They’re there because they love children, and they care about education,” Braun said.

Emanuel agreed.

“I happen to think Carol had a very good point here. It’s not only the quality of teachers. It’s parental involvement,” he said.

Watkins and candidate William “Dock” Walls also participated in the debate.

There will be two more televised appearances by the top four candidates next week.

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