HARRISBURG, Pa.—A Republican-penned bill that would pave the way for state takeovers of Pennsylvania school districts veering toward financial collapse has the state Senate's approval after several changes prompted the state's largest teachers' union to drop its opposition.

A spokesman for Gov. Tom Corbett couldn't immediately say Wednesday whether the Republican agrees with the changes made to the bill. It was approved, 27-21, on Tuesday. Only Republicans voted for it, while one Republican joined every Democrat in opposing it.

It would replace a piecemeal approach used in the past and is being spurred by fears of a wave of collapsing districts.

It still needs approval from the House as Corbett and Republican legislative leaders work to settle a package of high-priority legislation before lawmakers take their traditional summer break from Harrisburg.