It is disappointing to see Republicans playing politics in an effort to block the promotion of Justice Andrew McDonald to chief justice, replacing Chase T. Rogers. In 2012, a 33-3 Senate vote and 125-20 vote in the House of Representatives confirmed McDonald’s appointment to the state Supreme Court. That included substantial Republican support.

No evidence surfaced during the 13-hour confirmation hearing before the Judiciary Committee Monday to suggest that McDonald, though qualified to serve on the court, is suddenly unqualified to take the position of chief justice.

The nomination is in trouble. The Judiciary Committee voted 20-20, meaning the appointment moves on to the Senate and House with an unfavorable recommendation. The committee vote was along party lines with the exception of one Republican who recused herself and one Democrat who voted against McDonald’s elevation to chief justice.

With the chamber split 18-18, if Senate Republicans vote in lockstep they will block McDonald’s confirmation. Democrats have only 17 votes because Sen. Gayle S. Slossberg, D-Milford, will recuse herself from the vote. Her husband, attorney David Slossberg, claimed in a December 2014 court filing that McDonald could hold a grudge from an earlier case and wanted him disqualified from a pending Supreme Court case. McDonald said there was no conflict and participated.

Even approval in the House of Representatives, where the Democratic majority is 79-71, is not a certainty.

Two issues have made McDonald, 51, vulnerable to rejection — his close association to the man who appointed him, Gov. Dannel P. Malloy, and his pivotal vote in the 4-3 Supreme Court decision that struck down the final fragment of the death penalty in Connecticut. The latter issue could also scare off some Democratic support.

As to that first vulnerability, there is no denying that Malloy, in nominating McDonald both for the high court and now for the chief justice position, made an unusual choice in tapping a person so close to him and with a background more political than judicial.

McDonald served as director of legal affairs for Stamford from 1999 to 2002, when Malloy served as mayor. From 2003 to 2011, McDonald was the state senator from the 27th District, a time during which he chaired Judiciary and fought unsuccessfully for the repeal of the death penalty. When Malloy won election in 2010, McDonald joined the administration as general counsel, serving in that capacity until he entered the Supreme Court.

While unusual, McDonald’s path to the high court is not disqualifying. One could argue his trifecta — service in the legislative, executive and judicial branches — would give him a broad perspective in both assessing appeals and in carrying out his duties of administrative leader of the Judicial Branch.

This newspaper has consistently taken the position that the executive, be it the president or the governor, should be given substantial deference in judicial appointment choices. It is why we urged the confirmation of President Trump’s choice for the U.S. Supreme Court, Neil Gorsuch, even though we disagreed with much of Gorsuch’s judicial philosophy.

Lawmakers should only block a judicial nomination if evidence shows an appointee is unqualified. That is not the case with McDonald, as the overwhelming confirmation numbers in 2012 demonstrated.

On the death penalty, Malloy invited controversy with this choice. During his first term, Malloy, with McDonald a part of his administration, pursued and achieved repeal of the death penalty, a move our editorial page long pushed for. But in a calculated, morally inconsistent and legally weak political ploy, the legislation kept the death penalty in force for the 11 men on death row.

It was that inconsistency that the Supreme Court struck down as unconstitutional, sparing the death-row inmates. No surprise, then, to see Republican death-penalty proponents (and potentially some Democrats as well) calling out McDonald on this one.

Yet McDonald’s legal reasoning was sound and the majority agreed with him. His decision to vote as he saw fit on one particular appeal is not justification to deny him elevation to chief justice.

Two of our local state senators will cast key votes. Sen. Paul Formica of East Lyme and Sen. Heather Somers of Groton are fiscally conservative, pro-business Republicans, but they are not ideologues who hold slavishly to the party line.

We urge them to look past the politics, past their views on any particular issue and to set aside political disdain for our governor. If they act in accordance with their fundamental role — assessing McDonald’s qualifications — they should vote to confirm.