Topeka ? Legislators approved a $13 billion state budget Tuesday that uses federal stimulus dollars to protect higher education funding and avoids all but a modest reduction in aid to public schools.

But almost immediately, the Department of Revenue released preliminary figures showing that general tax collections for March were $57 million less than expected. The numbers suggest the spending that legislators approved can’t be sustained.

“It’s going to get bleaker,” said House Appropriations Committee Chairman Kevin Yoder, an Overland Park Republican. “We’re going to have to make further reductions.”

The Senate voted 35-5 for a bill containing the spending plan for the state’s 2010 fiscal year, which begins July 1. Hours later, the House approved the measure, 71-53, sending it to Gov. Kathleen Sebelius.

The final version of the budget bill was drafted by House and Senate negotiators, who reconciled dozens of difference between their chambers. But the Republican-controlled Legislature followed the Democratic governor’s plan to use $585 million in federal stimulus dollars to avoid a deficit in fiscal 2010.

Legislative researchers projected that the state would end fiscal 2010 with $172 million in cash reserves. But the estimate assumed revenues wouldn’t keep falling below expectations.

Instead, the Department of Revenue said, the state collected about $344 million in general tax revenues in March, when it expected $401 million. Legislative staff will have new budget projections by next week.

Legislators plan to begin their annual spring break Saturday, and officials and university economists plan to meet April 17 to issue a new financial forecast for the state. Legislators reconvene April 29 to wrap up their business for the year, and further budget revisions are likely.

Even with the stimulus funds included in the budget bill, legislative researchers said Tuesday, overall spending would decline in fiscal 2010 by $513 million, or 3.8 percent. The budget includes significant cuts in the operating budgets of agriculture, public safety and general government agencies, and it withholds promised aid to cities and counties.

Public schools and higher education came out significantly better because of the federal stimulus dollars, pleasing some legislators for the moment.

Kansas’ 295 school districts will lose about $25 million in base aid and special education funding, about 0.7 percent of their total aid of about $3.77 billion. Base aid will drop $33 per student.

House Minority Leader Paul Davis, a Lawrence Democrat, noted that the budget didn’t include $50 million in anticipated revenues from fees paid by developers for the right to build and operate new state-owned casinos in two counties. Democrats also noted that other revenue proposals from Sebelius had been ignored.

“We are cutting education funds when we don’t need to,” Davis said. “Why don’t we hold them harmless, if we have the ability?”