"You look at lower taxes. You look at job creation. We are stuck. We have been stuck in a terrible, overregulated economy for eight years. I mean stuck. Business stinks," the longtime Republican said in an interview with CNBC's "Power Lunch" the day after the election.
Trump's stunning victory defied polls and surprised the markets. In his victory speech early Wednesday, he said it was time for the nation "to come together as one united people."
Welch noted that because Republicans also retained control of Congress, Trump has an "awesome responsibility because there's no one else to point the finger at. So you've got to get a team together."
In her concession speech, Clinton congratulated Trump and told her supporters they owe him an "open mind."
A short time later, Obama pledged to ensure a smooth transition for the president-elect, and said, "We are all now rooting for his success."
Welch thinks Trump needs to forget every fight he had in the primary and general election and focus on who the best people are for the job.
"You can't have grudges in this game. You need talent. We will win with the best people," he said.
Welch supported Trump for president, but in October he yanked that support after Trump was caught on tape making crude comments about women.
Welch said he liked Trump's message, or policy ideas, but was concerned about the messenger.
"Every time I lurched forward in support, I'd lose the messenger. He'd do some wacky thing," he said.
That said, he thinks that President Trump will not necessarily be implementing some of what was talked about during the campaign, and suggests Trump might only deport "bad apples," not 11 million people, and could make better trade deals, instead of stopping trade.
"He's not going to shut down trade. He's going to get a better deal on TPP. He's going to do these things. This guy's a dealmaker," said Welch.
— CNBC's Jacob Pramuk contributed to this report.