CHICAGO (CBS) – Chicago mayoral candidate Rahm Emanuel has proposed what he characterizes as a city sales-tax cut. Opponent Gery Chico says it’s actually the biggest tax increase in the city’s history.

CBS 2 Chief Correspondent Jay Levine says it’s actually both: a 20 percent cut in the city’s portion of the current sales tax with an extension of the entire tax to some items not currently taxed.

Exactly what goods and services are we talking about? That’s the rub.

“You need a plumber? You’re going to pay the Rahm tax. You need a taxi cab? You’re going to pay the Rahm tax. You need to park your car? You’re going to pay the Rahm tax,” Chico said Friday, a day after he began hammering Emanuel on the issue at a mayoral debate.

Emanuel responded to Chico’s charges at an event in Uptown and again during an interview with CBS 2 at his campaign headquarters. Emanuel suggested he’s targeting the wealthy with his revenue idea.

“I’m for a lower sales tax for working families and making sure that people who rent charter jets for corporations, limos, join clubs like Saddle & Cycle do pay. They haven’t,” Emanuel said.

Emanuel says details of the tax would be negotiated with Springfield.

“What I’m being clear about is what are essential services versus what are some of these luxury items,” he told Levine.

Emanuel said he would not tax haircuts. Chico suggested otherwise at his own appearance at a Hyde Park barber shop. There, a mysterious limo showed up bearing a sign saying “Gery’s Tax Free Ride.”

Also Friday, Emanuel answered questions about a new radio commercial that features remarks President Obama made recently while bidding farewell to his Emanuel, his chief of staff.

“We are all very excited for Rahm as he takes on a new challenge for which he is extraordinarily well-qualified,” Obama said.

Emanuel says the ad is just a record of what the president said. He conceded that Obama is aware his comments are now being used in the campaign spot.

It’s not clear whether the president will make a formal endorsement in the mayoral race or this is as far as he’ll go. But Emanuel’s association with the president has been enormously helpful, especially among African-American voters.