Most of the media will tell you it was Sen. Trent Lott, by one vote.

TIME magazine has the correct answer, though it missed the point:

G.O.P. Senators said they were eager to have Lott back in the leadership, as he’s known as a clever back-room dealer and tactician on the Senate floor, which operates through a bizarre, complicated rules that at times outgoing Majority Leader Bill Frist didn’t seem to understand. “He’s the most effective leader I know,” said Arizona’s John McCain, who has won Lott’s support for his likely presidential bid. Minnesota’s Norm Coleman called Lott “the master of the Senate.”

The real winner is Sen. John McCain (Mav.-AZ), who will will formally open his 2008 presidential exploratory committee by tomorrow morning. 

McCain and Lott have an ongoing relationship.  While Rush Limbaugh suggests that the “Gang of 14” compromise on judicial nominations helped to usher in “the Schumer era,” that deal followed earlier efforts by Lott, who then remained behind the scenes for the final act.  (One of the more amusing aspects of the media coverage of Lott’s comeback are the quotes praising Lott’s skills, when it was his failure to be more than a dealmaker that helped ease him out of the Majority Leader’s chair following his praise for Strom Thurmond’s 1948 Presidential campaign.  But I digress.)

After getting the boot from leadership, he sought out McCain—who mouthed a couple of platitudes about Lott’s remarks—and adopted a McCain-ite agenda of reform and irritating the White House.

Since then, Lott has been telling his friends from the South that McCain is the candidate who can defeat Sen. Hillary Clinton in that region.  McCain has been headed South to tell audiences:

“I will tell anyone that of all the majority leaders we’ve had in the United States Senate, I believe that Trent Lott was the finest leader we’ve had.”

The only way it could be worse is if McCain believed it.  This much, however, must be said on Lott’s behalf:  he knew how to count votes better than Sen. Lamar Alexander (R-TN), who thought he had the race sewn up.

What does it mean?  Improbably enough, conservatives and libertarians will have an ear when it comes to issues like earmarks.  They will have less of an ear on judicial nominations and squashing free speech campaign reform than they might think.  And Sen./POTUS candidate McCain has an ally who can help shape the proceedings of the Senate to his liking without obvious fingerprints.