Mick Mulvaney, who is now Mr. Trump’s acting chief of staff, acknowledged when he was being confirmed for his previous job as budget director, that he had paid back taxes of more than $15,000 for a household employee whose payroll taxes he had not paid.
Former Representative Tom Price of Georgia, who in 2017 resigned as health secretary for using expensive chartered flights, had to defend stock trades that might have been impacted by his time in Congress during his confirmation hearing. And Steven Mnuchin, the Treasury secretary, was scolded by senators before being confirmed for failing to disclose $95 million of real estate assets on this ethics questionnaire.
In 2009, Timothy Geithner, who was former President Barack Obama’s first Treasury secretary, came under fire from Republicans for failing to pay more than $40,000 in federal taxes.
But many Republican senators were not overly concerned with Mr. Moore’s finances on Thursday.
“Steve has the right intellect, the right philosophy and the right background,” said Senator Kevin Cramer, Republican of North Dakota, and a member of the banking committee. “I’m not concerned — unless there are piles and piles and piles of these. People have tax issues from time to time, especially people who have had as many career changes as he has.”
Senator Richard Shelby, a member of the banking committee, said he was not familiar with details of the case, but suggested that Mr. Moore should be subjected to a full review of his past dealings if and when Mr. Trump formally nominates him.
“Scrub him,” Mr. Shelby said. “People got to do the right thing — and I assume he did — but it’s got to be scrubbed.”
Allies of Mr. Moore said that a simple tax snafu should not raise questions about his ability to help steer the United States economy. Macroeconomics, they said, is a much different beast than the tax code.
“Being a tax accountant is very different than being a good tax economist,” said Arthur Laffer, a prominent supply-side economist who recently wrote a book with Mr. Moore. “He’s very good on tax economics.”