Sen. Robert A. Zirkin (D-Baltimore County) said Wednesday night that he plans to vote in favor of repealing Maryland’s death penalty, which means the measure now has the support of a majority of members on a key committee.

Repeal legislation has died in recent years in the Senate Judicial Proceedings Committee, which is scheduled to vote Thursday on the latest version of the bill sponsored by Gov. Martin O’Malley (D). A majority vote by the committee would allow the bill to move to the full Senate, where there appears to be enough votes for passage.

Zirkin has agonized over how to vote, and he said in an interview Wednesday night that he remains “very torn.” But he said he had managed to separate his emotional response to people who commit heinous murders from his legal analysis of the issue.

“From an emotional standpoint, I want to kill these people myself,” Zirkin said. “But that’s a different question than whether, legally, the state should be involved in their death.”

Zirkin said he has also been heavily influenced by families of murder victims, who have told him that the current system does not provide closure. While the death penalty remains on the books in Maryland, the state has not executed a prisoner since 2005.

The state’s highest court ruled in 2006 that new regulations on lethal injection would have to be adopted for capital punishment to continue. Under O’Malley, a longtime death penalty opponent, that has not happened.

With Zirkin’s announcement, there are now 26 senators who are either co-sponsoring the repeal bill or who have said in interviews that they plan to support it.

In the Maryland Senate, 24 votes are required to pass a bill.

During Thursday’s committee voting session — and later on the floor — senators are expected to offer numerous amendments to the repeal bill. If any are adopted, that could complicate efforts to pass the legislation.

Repeal advocates say they are well-positioned to prevail in the House of Delegates if a bill passes in the Senate.

In most cases, a majority vote is required from a Senate committee to send a bill to the floor. Senate President Thomas V. Mike Miller Jr. (D) had said he would make an exception for the repeal bill if O’Malley could demonstrate he has enough votes in the full chamber. Doing so would require a rarely used procedural move.

Zirkin’s support provides a clearer path to passage for the legislation.