Colorado's Senate primaries are Aug. 10, but many voters are already mailing in their ballots.
The Republican primary between Weld County District Attorney and tea party favorite Ken Buck and former Lt. Gov. Jane Norton has gotten most of the attention, but the Democrats have a hotly contested race as well.
Learn all about the ups and downs of both races in this Roll Call midterm elections video special.
Produced by Andrew Satter.
Slideshow: Photos from Colorado's Senate Race
Go back to Roll Call's video page.