The U.S. Senate is to begin debate Wednesday on one of President Bush's judicial nominees - setting the stage for a possible showdown on the delaying tactic known as a filibuster.

The leader of the Republican majority in the Senate, Bill Frist, plans to bring to the Senate floor Mr. Bush's nomination of Priscilla Owen. A Texas Supreme Court justice, Ms. Owen was one of seven nominees blocked by Democrats during the president's first term.

If Democrats are successful again, Republicans say they will seek early next week to change Senate rules to limit filibusters, a parliamentary delaying procedure aimed at preventing a vote.

Opposition Democrats say changing Senate rules would drastically curtail the rights of the minority.

Talks seeking a compromise have not been successful.

Some information for this report provided by Reuters.