Since the Ames Straw poll in August, the Republican race has been defined by two things: the relatively low vote ceiling of former Massachusetts governor Mitt Romney and the rises and falls of a variety of conservative alternatives to him.

The chart below — provided by our friends at TargetPoint Consulting, a Republican media firm — tells the story. It’s a look at the total number of mentions — via television, blogs, radio etc — of each of the candidates from Aug. 15 on. Notice Romney’s steadiness and the peaks and valleys of everyone vying to be the not-Romney in the contest.