House Speaker Michael Madigan, a Chicago Democrat, wants Illinoisans who make more than $1 million per year to pay another 3 percent in taxes on that income.
He proposed the amendment to Illinois' constitution Thursday as a debate rages over whether the state should abandon its income tax structure that taxes everyone at the same rate, no matter how much he or she makes.
Madigan said his plan would raise an additional $1 billion -- about $550 per student -- and the proposal would direct that money to Illinois schools.
Madigan estimated there were 13,675 people in Illinois with adjusted gross incomes over $1 million in 2011.
"In a good year, I would be subject to this," said Madigan, a lawyer.
Illinois' income tax is 5 percent. It's scheduled to drop to 3.75 in January, but Democrats including Quinn favor replacing it with a progressive tax that taxes wealthier people at a higher rate.
Republicans are likely to vehemently oppose Madigan's surtax, arguing millionaires will just leave Illinois rather than face a new tax, costing the state tax money in other areas.
"People who are in high income brackets spend a significant amount of money on goods and services," state Rep. Tom Morrison, a Palatine Republican.
Lawmakers would have to approve the proposal this year, and it would end up on the November ballot if they do so before early May.
Madigan announced the idea just two days after wealthy private-equity investor Bruce Rauner won the Republican nomination for governor, setting up a race against Democratic Gov. Pat Quinn and his theme of raising the minimum wage to help the common man.
"I just happen to think that this is a good idea, I've given a lot of thought to this," Madigan said. "I think it makes sense. What we're doing here is calling upon people in Illinois that are well-equipped to provide support for education, which is available to everybody in the state."
A Rauner campaign spokesman was not immediately available for comment.
Quinn wouldn't express an opinion on the initiative, saying he would "take a look at the details."
• The Associated Press contributed to this report.