By Bob Benenson

When were the most senior GOP senators, come January, first elected?

a) 1972

b) 1974

c) 1976

d) 1978

er: c) In the aftermath of this year’s elections, the Republicans with the most Senate seniority are six-term incumbents Richard G. Lugar of Indiana and Orrin G. Hatch of Utah. Both were first elected to the Senate in 1976.

They will rise to the top of the Republican list because of the pending departures of the party’s two most-senior senators in the waning 110th Congress. Alaska’s Ted Stevens , whose 40-year tenure — he was first appointed in December 1968 — is the longest for any Republican in Senate history, was defeated for re-election by Democrat Mark Begich, the mayor of Anchorage. New Mexico’s Pete V. Domenici , who was first elected in 1972, decided to retire rather than seek a seventh term, and will be succeeded by Democratic Rep. Tom Udall .

The overall seniority list going into the 111th Congress is topped by four Democrats: West Virginia’s Robert C. Byrd , who was first elected in 1958 and is the longest-serving senator in history; Massachusetts’ Edward M. Kennedy , who first won a special election in 1962; Daniel K. Inouye of Hawaii, also first elected in 1962; and Patrick J. Leahy of Vermont, first elected in 1974. The seniority of Delaware’s Joseph R. Biden Jr. , first elected in 1972, would fit him in between Inouye and Leahy, but Biden was elected vice president on the ticket headed by first-term Illinois Sen. Barack Obama and will resign from the Senate prior to his swearing-in on Jan. 20.