Mayor John DeStefano Jr. and state Sen. Martin Looney took one last chance Wednesday night to criticize each other for stadium plans, scandals and magnet schools as they squared off in a radio debate, their final scheduled joint appearance before Tuesday’s Democratic mayoral primary.

The four-term incumbent and his challenger sat just feet away from each other at the Hamden studio of WELI, exchanging jokes and stories during some commercial breaks. While there was some tension in the air as the candidates refuted each other’s arguments, the debate was relatively peaceful as the candidates reiterated their campaign platforms one last time for the voters.

Dressed in a shirt and tie, DeStefano trumpeted his administration’s successes and what he called the city’s improved standard of living over the past eight years.

“We are blessed to live in a community where people have opportunity to do so many wonderful things,” DeStefano said.

Looney repeated his assertion that DeStefano has failed to take advantage of opportunities during his administration and called for a new beginning in City Hall.

“New Haven should not be compared to Hartford and Bridgeport and Waterbury,” Looney said. “New Haven is the seat of a world-class major university. Our peer cities in this region are Providence and Cambridge, and we lag far behind them.”

The candidates clashed on education issues, as they have in the past. DeStefano said he supported an expansion of the city’s magnet school program, which attracts 900 suburban students to the school district. He said the racial diversity that occurs from this mixing is invaluable.

Looney contended that while magnet schools have their place, the city should focus on the neighborhood schools that he says have been neglected by the administration’s magnet emphasis.

The two also disagreed on teacher salary levels. Looney has promised a pay raise to teachers, and has been endorsed by the local teachers’ union. He said Wednesday he plans to pay for the raise by cutting the number of administrators employed in the school.

DeStefano defended the number of administrators, saying it was highly appropriate for a city with as many schools as New Haven.

Looney once again defended his plan to build a stadium in or near downtown for minor league baseball, soccer and lacrosse. He said he believed the stadium could bring up to 350,000 people a year into the city.

The senator also repeated his pledge, first made Tuesday, to call for a voter referendum on the stadium proposal before ground is broken.

DeStefano disagreed with the plan, saying that a stadium would not generate jobs, tax revenues or economic development. He pointed to Bridgeport as a city where a new stadium was not accompanied by nearby development.