That does not appear to have happened, and now opponents of the death penalty have hastily formed a group, Nebraskans for Public Safety, to campaign against a repeal. The group has run television and radio ads, urging voters to “Decline to Sign.”

“If someone wants your signature to bring back a failed system, say no,” the narrator intones.

Danielle Conrad, an American Civil Liberties Union director and former state senator who is leading Nebraskans for Public Safety, said in an interview that the ending of capital punishment in the state not only had been “a fair process, it went through a very deliberative process.”

“The petition is kind of a head scratcher from our perspective,” she said. “These petitions all offer false promises. Even if proponents are successful with procuring signatures and successful with procuring ballot access and successful at the polls in November 2016, that still gets us no closer to carrying out executions in Nebraska.”

Nebraskans for Public Safety has raised $400,000 from the Proteus Action League, a national human rights organization that financially backs efforts to abolish the death penalty.

“Even if we brought it back tomorrow, we’d be years away from an execution,” said Stacy Anderson, until recently the executive director of Nebraskans for Alternatives to the Death Penalty, which was founded in 1981. “We don’t have access to drugs. We’re not actually solving anything by bringing it back.”

But for some Nebraskans, the petition drive is an effort to correct what they see as a leftward drift in the Legislature.

“People here need to quit bowing down to the left,” Rory Ashker, 43, a truck driver, said as he signed the petition in Norfolk. “The left is out of control. People who commit murder in this state need to be taken down, and the death penalty is the only way to do it.”