Jeb Bush flashed a feistier edge. Ben Carson defended a biography under siege. Ted Cruz trumpeted his opposition to illegal immigration amnesty. And Donald Trump sniped at his rivals.

A smaller cast of characters gathered Tuesday in Milwaukee for the fourth presidential showdown of the year. But the eight candidates on the main stage proved just as desperate as ever to stand out from the crowded field.

Bush, the former Florida governor, tried to shake off three flat performances in the previous debates with a feisty, aggressive style. He bristled at the debate’s start when another rival tried to interrupt him – “I’m going to get my question now,” he declared – and cast himself as Democratic frontrunner Hillary Clinton’s biggest nemesis.

“I’m going to fight as hard as we can to make sure we shift power away from Washington,” said Bush, who is trying to reboot his campaign with a focus on his eight years in Florida’s top job. “People are really struggling right now. Jobs are being created. But they’re lower income jobs.”