SPRINGFIELD, Ill. — Gov. J.B. Pritzker urged Illinois legislators Tuesday to “let the people vote” on his constitutional amendment that would dump the state’s flat-rate income tax structure for one that takes a bigger bite from the wealthy .

The billionaire contends his proposal would mean the same tax bill or a tax cut for 97 percent of Illinoisans; higher taxes only on those making more than $250,000; and $3.4 billion in additional annual revenue for the deficit-riddled state. It would replace the state’s current 4.95 percent flat tax rate.

It’s unclear if Pritzker has the support from three-fifths majorities in both House and Senate, which must approve it before the question is put to voters in November 2020 at the earliest.

Illinois has billions of dollars of debt in underfunded pensions, overdue bills to vendors and contractors, and insufficient revenue to cover existing expenses, prompting a predicted $3.2 billion shortfall at the end of the next budget year in June 2020.

In addition to approving the constitutional amendment, Pritzker said he wants lawmakers to set final tax rates before their scheduled May 31 adjournment. That would give voters time to determine how a tax change would affect them before heading to the voting booth in 18 months.