From NBC's Mark Murray
As a reminder that the political season isn't over just yet, the National Republican Senatorial Committee is airing a tough TV ad in Georgia against Senate challenger Jim Martin (D).
The ad's kicker tries to advance the argument that a Democratic victory in the December 2 run-off could give the Democrats a filibuster-proof majority in the Senate. "With unchecked power hanging in the balance, Georgia can't afford another liberal like Jim Martin in Washington." (Politico's Ben Smith also smartly points out that the ad doesn't mention Obama at all.)
Meanwhile, in advance of McCain stumping tomorrow for incumbent Sen. Saxby Chambliss (R), Democrats have unveiled a new Web video noting that McCain denounced the controversial TV ad that Chambliss aired back in 2002 to help topple Democrat Max Cleland.