Although he no longer serves as the Judiciary Committee’s top Republican, Sen. Arlen Specter (D-Pa.) on Wednesday appeared to relish his new position as backbencher as he freely questioned Supreme Court hopeful Sonia Sotomayor without the pressures of his former party’s conservative base.

While there were questions about how Specter would handle sitting at the end of the Judiciary panel’s dais for the first time in decades, it quickly became clear that the Pennsylvanian still embraces being one of the Senate’s veteran legal minds. Specter, facing a strong primary challenge, bolted the GOP in April and in so doing gave up his seniority on Judiciary, where he served as chairman during the previous two Supreme Court nominations.

Specter, who had become the darling of conservative judiciary groups, on Wednesday questioned why his former Republican colleagues were focusing on Sotomayor’s 2002 comment that a “wise Latina— would sometimes arrive at better conclusions. And he offered kind words to President Barack Obama’s choice for the high court: “You have held up very well through all of the proceedings in the Senate. … You have shown humor and intellect and charm and also modesty.

“Now on to the issues. … I begin with an area of cases which the court has decided not to decide,— Specter then said.

Specter veered far off the path of GOP Senators, who have pressed Sotomayor over hot-button issues such as abortion and race.

Specter, during his term, delved into the minute details of legal theory with phrases like “congruence and proportionality— — an obscure test used by the Supreme Court to evaluate whether Congress has the authority to legislate over a particular issue.

He also waded into legal issues such as the separation of powers, allowing televisions in the court, the relatively few number of cases the Supreme Court has considered, the Voting Rights Act and others.

Specter, a former prosecutor, has long been viewed as a tenacious questioner who favored policy over politics. He had to lobby Republicans to give him the gavel in early 2005 to oversee what’s arguably the Senate’s most partisan committee.

Indeed, Specter only was able to win the chairmanship after conservatives and the Bush administration extracted promises from the relatively moderate lawmaker that he would back the administration’s hard-line conservative nominees.

Specter was responsible for shepherding the nominations of Chief Justice John Roberts in 2005 and Justice Samuel Alito in 2006, often sparring bitterly with now-Chairman Patrick Leahy (D-Vt.), who was then the panel’s ranking member.

And earlier this year, Specter spearheaded an ultimately failed attempt to mount Senate opposition to the nomination of Eric Holder to become attorney general.

A source close to Specter acknowledged that not having the constraints of the chairmanship or ranking member post has liberated him.

“It allows him to delve into the issues he really cares about rather than doing something for party’s sake. I don’t know if he’d get to use the term congruence and proportionality’ as much if he was chairman,— this source said.

That’s not to say that he’s become any less cantankerous, particularly with a nominee who seems unwilling to answer his questions directly. Specter repeatedly chastised Sotomayor for not answering his queries.

“Well I can tell you’re not going to answer, so let me move on,— he said at one point, while later he quipped, “I’m not commenting about your answers but your record is exemplary. … You’ve studied the questions and you’ve studied the record and your qualifications as a witness are terrific and in accordance with precedence. You’re following the precedence very closely.—