Leahy, 69, will be in charge of keeping senators to their allotted 30 minutes for questions, tamping down the inevitable showboating and issuing stern warnings to any protesters who get out of hand.

It's good to be chairman, by the way: He can allot himself all the time he wants to rebut points Republicans try to make or to ask clarifying questions of the nominee. Leahy was a state prosecutor for eight years before coming to the Senate. The grandfather of five is an avid photographer seen at previous hearings snapping pictures of news photographers as they snap photos of him.

Ranking Republican Jeff Sessions of Alabama.

Taking his first turn as the lead Republican at a Supreme Court hearing, the 62-year-old Sessions will sit next to Leahy and, in broad terms, try to reassure the vanquished GOP base that their interests are being represented in this most visible forum.

Sessions wants to know whether Sotomayor allows personal views, not just the law, to influence her rulings. He has raised doubts about her support for the constitutional right to keep and bear arms and her association with a Puerto Rican civil rights group before she became a federal judge 17 years ago.

But conservative critics of Sotomayor have been unable to get the Senate's 40 Republicans to stand together against her, and Sessions has said he doesn't "sense a filibuster in the works" to block her confirmation.

Personally and politically, he's got big shoes to fill and a delicate line to walk in this role. Sessions is succeeding the sharp-tongued Specter, chairman at the previous two Supreme Court hearings.

Sessions, in his third term, has plenty of experience grilling witnesses; he's a former federal prosecutor. But he has stumbled over issues of race. Comments he allegedly made sank his own nomination by President Ronald Reagan to be a federal judge.

THE DEFENDERS

Senate Democrats Dick Durbin of Illinois and Charles Schumer of New York.

They're Obama's guys, for different reasons.

Durbin, in his third term at 64, is the president's chief ally in the Senate and served with him during Obama's meteoric rise. Schumer, 58, and in his second term, represents Sotomayor's home state, is thus her sponsor. By tradition, he will introduce her to the committee when the hearings open.

Durbin and Schumer have leadership positions in their party, are regarded by Republicans as fierce partisans and are fond recipients of news coverage. They share a house with other members of Congress in Washington while away from their families.

THE PATRIARCH

Sen. Orrin Hatch, R-Utah.