I asked them and here is the response:
Dear Bill,
Tennessee is fortunate because it has had many great leaders, statesmen who rise above the fray to get things done. This is a recognition that their willingness to step up and overcome challenges is an important quality for the next governor to have, and this isn’t an endorsement of everything each of these leaders did or a comparison of ideologies. Many names could have been included, but with only 60 seconds we chose to list three Tennessee governors who all made a big impact in getting things done for Tennessee, and a Senator who has a similar background to Mayor Haslam – led a business, ran a city – and who in his first term has distinguished himself in the Senate as a leading voice on finance and banking issues.
Sincerely,