SPRINGFIELD — Voters have rejected a proposal to abolish Illinois’ flat-rate income tax for one that would take a greater share from wealthier taxpayers.The outcome of Tuesday’s vote handed Gov. J.B. Pritzker the first major defeat of his 22-month tenure. The Democrat campaigned on establishing a progressive tax which he said would make tax payments the same or lower for 97% of the state while those making more than $250,000 would pay on a graduated scale.Dubbed the “Fair Tax” by Pritzker and supporters, it was to generate …