Republican Sen. Ron Johnson paid little in state income taxes in 2017 compared with other years, despite reporting income of at least $450,000.
Johnson, who has not said yet whether he will seek a third term next year, is a top target for Democrats, who have 11 candidates declared for the race in the presidential battleground state.
Johnson paid $2,105 in state income taxes in 2017, the Milwaukee Journal Sentinel reported Thursday. That stood out for Johnson, who on average paid more in state income taxes over the past 10 years than any of the top Democrats seeking his Senate seat, the newspaper reported based on a review of tax records.
Johnson's average state income tax payment over that time was $60,000 a year, or about 30 times more than he paid in 2017.
There are many reasons why Johnson could have escaped paying higher taxes in any given year, including business losses, a special one-year deduction and a large charitable contribution, said Andrew Reschovsky, a tax expert and professor emeritus of economics and public policy at the University of Wisconsin-Madison's La Follette School of Public Affairs.
"There are a number of ways in which one can reduce your Wisconsin income tax liability perfectly legally," said Reschovsky, who has no direct knowledge of Johnson's tax payments.
Johnson's campaign provided few details and refused to release his federal income tax returns.
"The senator had a smaller tax payment because he had less income to report in 2017," Johnson's spokeswoman, Vanessa Ambrosini, told the newspaper. Ambrosini didn't immediately respond to a message from The Associated Press.
If Johnson does run for a third term, he will provide the press with a similar level of "tax detail" as he has in the past, Ambrosini told the Journal Sentinel.
During his 2010 campaign, Johnson released three years' of federal tax returns. He provided no returns in 2016.
The Democratic candidates' income tax payments also revealed some anomalies.
State Treasurer Sarah Godlewski didn't pay any state income taxes in either 2017 or 2018. Her campaign provided details about why, saying she eliminated her state tax liability through charitable contributions, state economic development credits and venture investments in new companies that were not yet profitable.
Lt. Gov. Mandela Barnes paid no income tax in 2018 and was on the state's Medicaid program while he was unemployed and running for lieutenant governor.