CHICAGO (Reuters) - The Illinois Senate on Sunday rejected Governor Bruce Rauner’s changes to an education funding bill, sending the measure to the House, where similar action is uncertain, and leaving school districts guessing when state-aid dollars will begin flowing.

FILE PHOTO: Illinois Governor Bruce Rauner talks to the media after a meeting with U.S. President Barack Obama at the White House in Washington December 5, 2014. REUTERS/Larry Downing/File Photo

The Democratic-controlled Senate voted 38-19 to override the governor’s amendatory veto, which proponents of the measure said resulted in substantial revisions.

Ahead of the Senate vote, the Republican governor reiterated his opposition to the bill as being a “bailout” for the Chicago Public Schools (CPS), the nation’s third-largest public school system.

“The Senate has a choice: send more money to the neediest school districts across the state or vote to send Chicago another bailout,” Rauner told reporters in the state capitol.

Data released by his office indicated his veto action would result in CPS receiving $463 million less than what it was allocated under the bill.

The Democratic-controlled House, which passed the bill in May in a 60-52 vote, returns to session on Wednesday. It was unclear if the chamber would be able to muster the 71 votes required for an override.

Without a new school funding formula in place, Illinois for the first time missed its initial August payment to schools last week. [nL1N1KW1K7]

The fiscal 2018 budget enacted by the legislature in July over Rauner’s vetoes required the enactment of a so-called evidence-based education funding formula before $6.7 billion in state aid could be distributed to Illinois’ 852 school districts.

That stoked fears some districts would not be able to start classes on time or would be forced to tap reserves or borrow to stay open. CPS on Friday unveiled a $5.7 billion fiscal 2018 budget that relies on a $300 million state funding boost, as well as $269 million in unidentified local money. [nL1N1KX1GT]

A failure to override the veto in the House would kill the bill. Rauner said lawmakers should quickly find another solution if the bill dies.

“This is too important to let partisan games get in the way,” he said.