Washington - The embattled Republican Party captured a 41st US Senate seat with the re-election of Senator Saxby Chambliss in Tuesday's Georgia runoff.

The victory for Chambliss with 57 to 43 per cent with nearly all the votes counted denies president-elect Barack Obama's Democratic Party a potential super-majority in the 100-seat Senate.

The rules in Congress' upper chamber require 60 votes to end debate before voting on many issues, allowing a minority of at least 40 senators to block legislation by a parliamentary manoeuvre, a so- called filibuster.

Chambliss, who fell just short of 50 per cent in the November 4 election, defeated Democratic nominee Jim Martin with relative easy, after a closely watched, four-week run-off race that saw a parade of national figures.

The defeated Republican presidential ticket - Arizona Senator John McCain and his running mate, Alaska Governor Sarah Palin - and former New York mayor Rudy Giuliani were among the centre-right party's top attractions who campaigned for Chambliss.

Republican National Committee Chairman Mike Duncan addressed Chambliss' victory rally in a sign of the party's focus on the Georgia race. Chambliss claimed to have had Republican volunteers from 43 states.

Turnout for the lone Senate race was about half the rate of the general election. Georgia's requirement of runoffs for congressional offices in the absence of an outright majority is a rarity among the 50 US states.

Obama, who led a Democratic victory last month that saw the centre-left party expand its majorities in Congress, kept his distance from the runoff, recording endorsements for Martin but not appearing personally in Georgia.

The only Senate seat to be decided is in Minnesota, where a recount is underway after Republican incumbent Norm Coleman won by only a few hundred votes against Democrat Al Franken, a well-known comedian.