The Colorado Senate race between appointed Democratic incumbent Michael Bennet and Republican Ken Buck will likely be one of the closest (if not the closest) contests this Tuesday, if recent polls are accurate. CNN/Time has Buck with a one-point lead, while Colorado Pols/RBI Strategies has Bennet up by a point. For all intents and purposes, this race is completely tied just days before the election.

CNN/Time (PDF) (10/20-26)
Michael Bennet (D) 46
Ken Buck (R) 47
Other 4
No Opinion 3

Colorado Pols/RBI Strategies (10/24-26)
Michael Bennet (D) 43
Ken Buck (R) 42
Maclyn Stringer (L) 3
Bob Kinsey (G) 1

This one has been relatively close for a long time, and seems to have only tightened as the election nears. That is why this should be one of the most closely watched races on Tuesday.