President Barack Obama on Tuesday blasted Republican presidential nominee Donald Trump, telling voters in Ohio that Trump will not be a champion for the working class, despite those voters being a key part of the real estate mogul’s support base.

Campaigning for Democratic presidential nominee Hillary Clinton in Columbus, Obama tore into the real estate mogul’s history of stiffing workers at his businesses and evading federal taxes, arguing that it is incongruous with Trump’s message that he will be a champion for workers.

“This guy?” he said, in disbelief over Trump’s appeal to working class voters. “Don’t be bamboozled. Come on! That guy had never worn a baseball hat until he started selling them to make some money. Come on!”

Obama characterized Trump as “somebody who has spent 70 years on this Earth showing no regard for working people.”

“If you’re a working person, if you’re out there working hard every day, punching the clock, working hard every day,” Obama continued, “the notion that this guy is your champion, the notion that this guy is going to fight for working people, when his entire life, he didn’t have time for anybody who wasn’t rich or wasn’t a celebrity, who wouldn’t let you in to one of his hotels unless you were cleaning the room, wouldn’t let you on to one of his golf courses unless you were mowing the fairway? Come on!”

He blasted Trump for not paying federal income taxes, which the businessman has boasted was “smart.” On Monday, the New York Times reported that Trump used a “legally dubious maneuver” to avoid paying federal income taxes for years, a loophole that even his own lawyers advised would invite suspicion from the IRS.

Obama also dismissed the notion that Trump’s history of racism and misogyny would change. To justify their support of Trump, many Republicans have argued that he would moderate his behavior and offensive remarks if elected president.

“Who you are, what you are, does not change when you occupy the Oval Office,” Obama said. “The only thing this office does is magnifies who you are. It amplifies who you are. It shows you are. If you disrespected women before you were elected, you will disrespect women once you’re president.”

Editor’s note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims — 1.6 billion members of an entire religion — from entering the U.S.