"To be honest with you, that infuriates me," Wurzelbacher told "Nightline." "It's not right for someone to decide you made too much -- that you've done too good and now we're going to take some of it back."
"That's just completely wrong," he added.
Wurzelbacher conceded today that he is not in danger of being hit with the higher tax rate. He acknowledged that he wants to buy a plumbing company for $250,000 to $280,000. That wouldn't be how much profit he would make from the firm.
He would make much less, he said.
That would seem to indicate that Wurzelbacher would not be subject to Obama's proposed tax increase from 36 percent to 39 percent for those making more than $250,000 per family. Instead, he would be eligible for a tax cut that Obama is proposing.
Nevertheless, the plumber said people shouldn't be "punished' for success even if you become a billionaire.
"I don't like it," said Wurzelbacher. "You know, me or -- you know, Bill Gates, I don't care who you are. If you worked for it, if it was your idea, and you implemented it, it's not right for someone to decide you made too much."
Wednesday night's debate became very personal for Wurzelbacher.
"You were going to put him in a higher tax bracket, which was going to increase his taxes, which was going to cause him not to be able to employ people, which Joe was trying to realize the American dream," McCain said to Obama.
The Arizona senator then looked directly into the TV camera and said: "Joe, I want to tell you, I'll not only help you buy that business that you worked your whole life for and I'll keep your taxes low and I'll provide available and affordable health care for you and your employees. And I will not stand for a tax increase on small-business income."
Wurzelbacher would not reveal whom he'll cast his ballot for Nov. 4.
"That's a personal decision. Myself and the button I push will know that answer," he said.
He encouraged voters to "be educated" before selecting a candidate.
"Don't sit there and take someone else's opinion. Listen to them. Find the information out for yourself," Wurzelbacher said.
ABC News' Chris Bury contributed to this report.