JEFFERSON CITY – The Missouri Senate passed a scaled-back sales tax increase for transportation funding Tuesday as supporters sought to make the bill more palatable to the chamber's Republican majority.

Senators voted 22-10 to send the proposed constitutional amendment to the House. It would levy a three-fourths cent sales tax if approved by voters at the November election. The state sales tax would rise to just below 5 percent, but in most areas the overall tax is higher.

House members backed a 1-cent sales tax increase earlier this month. Now the two chambers must agree on an identical version to send the issue to the ballot for voter approval.

The Senate's version is projected to generate $534 million annually during the 10-year lifespan of the tax. A 1-cent sales tax would pour $720 million per year into the state's coffers.

"It doesn't cure all the problems, but it does take care of a lot of issues," said sponsoring Sen. Mike Kehoe, R-Jefferson City. "It's a compromise."

The Missouri Transportation Department says that it takes $485 million annually to maintain roads in their current condition but that the state's construction budget is projected to dip to $325 million in 2017.

The decline is due to a variety of factors. Federal highway funding has become more uncertain and fuel taxes have flattened out, partly because of more fuel-efficient vehicles. A bond-financed surge in construction during the last decade has now dropped off, while the payments continue. Construction costs have also risen.

Transportation Department Director Dave Nichols said after Tuesday's vote that he was "excited" lawmakers were continuing to discuss the proposal. When asked about the reduced amount, he said it's up to lawmakers to decide how much money the department can put to use.