Testimony ended Friday in the Judiciary Committee with Chairman Arlen Specter, R-Pa., criticizing Democratic senators.
While most observers believe Judge Samuel Alito Jr. will be confirmed to replace the retiring Associate Justice Sandra Day O'Connor, both parties are using the debate to posture for November elections, The New York Times reports.
Democratic leaders say Alito is an example of the right-wing's grip on elected officials, eventually leading to weakening of abortion and civil rights and granting the president too much power during wartime.
Republicans say Alito is a mainstream jurist and accuse Democratic leaders of playing politics with the Supreme Court.
The committee is expected to vote next week to send the nomination to the full Senate for debate.
Democratic senators want that to be delayed until after Wednesday when leaders meet to discuss a plan.
Republicans call that another political ploy.
Both liberal and conservative-leaning groups said Friday they will create commercials about the issue, not to sway senators, but to further the political debate.