History is a favorite subject of Maryland Senate President Thomas V. Mike Miller Jr. (D-Calvert). And he feels his vote against same-sex marriage may put him “on the wrong side” of it.

“I don’t think this is civil rights, but this is history,” Miller, 69, told his colleagues Thursday night after they passed the bill, paving the way for Maryland to join seven states and the District in letting gay couples wed.

Maryland Senate President Thomas V. Mike Miller Jr. addresses the Senate in Annapolis on Feb. 23 during debate on the gay marriage bill. (Patrick Semansky/AP)

Miller — the longest-serving president of any state Senate — is fond of sharing trivia and stories about the venerable body of state legislators he joined in 1971.

On Thursday, he told colleagues that he could not bring himself to help undo words in state law he helped write in 1972, which until this week defined marriage as between a man and a woman.

“I was married, had four children in diapers,” Miller said. “It was a very easy vote for me to say marriage is between a man and a woman.”

The irony is that Miller’s name will appear as lead sponsor on the Senate version of legislation he voted against and that he has promised to vote to repeal if and when opponents are able to gather enough signatures to petition the measure to referendum in November.

Under protocol in Maryland, the president of the Senate and the speaker of the House sponsor legislation proposed by the governor.

After publicly opposing same-sex marriage for most of his political career, Gov. Martin O’Malley (D) in the last year took on the issue as his own, and introduced it last month as part of his legislative package.

Maryland Gov. Martin O'Malley, center, greets supporters and members of the House of Delegates after the House passed a gay marriage bill Feb. 17. (Patrick Semansky/AP)

“I’m prepared to sign it because I believe that the way forward among people of many different faiths is always in the direction of greater respect for the equal rights for all,” O’Malley said at a discussion in the District hosted by Politico.

Asked about the evolution of his thinking on the issue, the governor said he had long “misjudged” the political solution to the hot-button issue.

“I think good leaders, who are progressive leaders, always try to be a force for building consensus that moves us forward.

“For a long time, I though that consensus point was civil unions. I was mistaken, I misjudged, the public moved forward more quickly on this issue than I had thought we would as a people.”