Lamar! had to vastly outspend Bryant, who outperformed him in EVERY single campaign appearance. Lamar! was very tired during the campaign and had to keep repeating that he'd be a reliable vote for Dubya (which he hasn't been). Lamar! never had served in Congress and it was embarrassing watching him try to debate Bryant, who was extremely well-versed on the issues. Lamar! had the opportunity to serve in the Senate in 1984 when he was still important and he turned his back on the people of Tennessee. He didn't deserve a reward for giving us a Senator (and ultimately Vice-President) AlGore.
Lamar Alexander was the logical choice at the time. He had far greater name I.D. and Tennssee was less Republican than it is now. He won the general election by a fairly comfortable margin. You are right, however, that his record in the Senate has been thoroughly mediocre, even dissapointing.
But that was then and this is now. Any informed research into this race based on logic would conclude that Ed Bryant is the best choice for 2006.