It may be weeks or even months before U.S. President Barack Obama announces his first appointment to the United States Supreme Court.  But, he is already getting a lot of advice from members of Congress about a possible replacement for retiring Justice David Souter.

The newest Democrat in the U.S. Senate - former Republican Arlen Specter - is urging the president to add to the diversity of the court.

"Women are underrepresented on the court," said Arlen Specter. "We do not have an Hispanic.  African-Americans are underrepresented."

During an appearance on the NBC television program Meet the Press, Specter said he would also like to see the president reach beyond the federal court system - the traditional training ground for members of the high court.

"I would hope that he would look beyond the Circuit Courts of Appeals, which now populate the Supreme Court, and pick someone with greater world experience," he said.

One name raised as a possible nominee is Secretary of Homeland Security Janet Napolitano.   She has never been a judge, but has served as governor and attorney general of the state of Arizona.  During an appearance on the Fox News Sunday program, Napolitano was asked is she is interested in a spot on the Supreme Court.

Napolitano brushed off the suggestion, noting she has plenty to do right now overseeing the federal government's response to the H1N1 flu.

"I think the president has many, many excellent choices before him and that is his choice to make," said Janet Napolitano.

The replacement of Justice Souter is not likely to radically change the ideological composition of the court.  Souter was considered a moderate who often sided with the more liberal justices. 

Republican Senator Orrin Hatch - like Senator Specter - is a former chairman of the Senate Judiciary Committee.  He told ABC's This Week program that he expects the president will pick someone with a liberal record on major issues.

"I am hoping he will pick someone with great dimension," said Orrin Hatch. "We all know he is going to pick a more liberal justice."

The current chair of the Senate Judiciary panel - Democrat Patrick Leahy - says he will do all he can to make sure a new justice is confirmed by the time the Supreme Court reconvenes on October 5.

"We certainly will have somebody in place," said Patrick Leahy. "It would be irresponsible if we did not have somebody in place by the beginning of the October session."

Leahy also appeared on ABC's This Week.