US: If the Senate majority leader Bill Frist and the Republican majority prevail in their procedural move, the Republicans will be able to force a vote on a judicial nomination from the president with a simple majority instead of three-fifths of the Senate.
Republicans hold 55 of the seats in the chamber and until now they have needed 60 votes to end debate and force a vote. But Republicans believe they have worked out how to use the chamber's rules so that only a simple majority - 51 votes - would force an up-or-down vote.
To get there, Republicans will have to evade a requirement that they have a two-thirds vote - 67 of 100 senators - to change the chamber's rules.
Republicans will argue that they are attempting to set a precedent, not change the Senate rules, to disallow the use of filibusters as a delaying tactic on judicial nomination. Democrats contend that the Republicans are essentially breaking the rules to change the rules.
The rule change Frist is seeking to bar the use of the filibuster for judicial nominations has been dubbed the "nuclear option", because of its potential to disrupt the Senate and shatter what little comity remains there between Republicans and Democrats.