The battle for the No. 3 Senate leadership post between Tennessee Sen. Lamar Alexander and North Carolina's Richard Burr is heating up in advance of tomorrow's vote. The race for chair of the Senate GOP Conference intensified this week when Texan Sen. Kay Bailey Hutchison bowed out.

Senate sources said they had heard she was making calls on behalf of Alexander, but an aide said that those rumors were "100 percent not true" and that she wasn't taking sides in the race. Hutchison spokesman Matt Mackowiak confirmed that the Texan isn't whipping votes for either candidate.

"Senator Hutchison has said she will not endorse or help either candidate for conference chair," said Mackowiak. Some in the leadership expect Alexander to win, replacing Sen. Jon Kyl. Kyl is expected to move up to Senate whip to replace retiring Sen. Trent Lott, who is expected to open a consulting and lobbying shop in Washington.

Alexander is credited with being a good party spokesman—the main job of the conference chair—and a tremendous fundraiser for the party. He also has a long Washington résumé and has run for leadership posts before. Rookie Burr is no slouch, however. His team says he is excellent at policy, has keen political instincts, is an able legislator, and is a good fit for the job as spokesman. They also dismiss any suggestion that he hasn't been working 24/7 to woo colleagues.

"Since last week, Senator Burr has been reaching out to his colleagues and has been working hard for every vote," says a Burr associate. A leadership aide said a Burr victory would "be a major upset."