Gov. Pete Ricketts of Nebraska vetoed a bill on Tuesday that would abolish the death penalty in the state, testing the strength of a bipartisan group of lawmakers who said they would try to override his decision.

“This is a matter of public safety,” Governor Ricketts said at a news conference at the State Capitol in Lincoln. “It’s also a matter of making sure the public prosecutors have the tools they need to put these dangerous hardened criminals behind bars.

“We have 10 inmates on death row — we don’t have hundreds,” he said. “We use it judiciously and prudently, and therefore we need to retain it. I urge all the senators who are making this vote, please sustain my veto.”

Lawmakers quickly scheduled a vote to try to override the governor’s veto for Wednesday afternoon.

If the lawmakers are successful, Nebraska will become the first largely conservative state in more than 40 years to strike down the death penalty. Republican legislators who have voted in favor of abolition said they believed the death penalty was inefficient, expensive and out of place with their party’s values. Other lawmakers cited religious or moral reasons for their support of the death penalty ban. Eighteen states and Washington, D.C., have banned the death penalty.