Gov. Dannel P. Malloy on Thursday nominated his legal counsel and longtime friend from Stamford, former state Sen. Andrew McDonald, to Connecticut's State Supreme Court.

If confirmed by the General Assembly, where he served eight years, the 46-year-old McDonald would be the state's first openly gay appellate jurist, Malloy said.

"In my estimation, Andrew possesses an exceptional ability to understand, analyze, research and evaluate legal issues," said Malloy, who called McDonald a thoughtful person who is "highly principled and ethical."

Shortly after his nomination was announced, Republican leaders in the state Senate announced their support of their former Democratic colleague.

"While Andrew and I have had considerable political differences over the years, I have always respected his commitment to public service and the law," said Senate Minority Leader John McKinney, R-Fairfield. "He is qualified and I am confident he will uphold the state constitution and carry out his responsibilities as a Supreme Court Justice with the highest degree of impartiality and integrity."

As co-chairman of the General Assembly's Judiciary Committee, McDonald was a chief proponent of same-sex marriage in Connecticut and an earlier law legalizing civil unions for gay and lesbian couples. For most of his legal career McDonald worked as a litigation partner for Pullman & Comley LLC, where he chaired the law firm's appellate practice. He also served as director of legal affairs and corporation counsel for the city of Stamford, from 1999 to 2002. That was during Malloy's tenure as mayor of Stamford.

McDonald recalled on Thursday being humbled by the experience of first arguing before the state Supreme Court.