I agree with your view. Kansas is a moderately conservative state. My former state of residence, Idaho, is a conservative state.
What makes for unpredictability here in Kansas is the uneasy truce between the economic conservatives and the social conservatives. A lot of economic conservatives are embarrassed by their social conservative colleagues and will jump ship to support a Democrat whose economic views are not too wacky because of the social issues. I think that backlash against social conservatism is what is hurting Brownback right now. Several economic conservatives that I know applaud some of Brownback's actions but are still very cool toward him because of his linkage to the social conservative wing of the party. I think that most of them are looking for any reason that they can find to vote against him. I think Brownback is facing a serious challenge this election.
IMO Roberts is still suffering from the residency issue which he handled poorly. While I believe that Roberts could be improved upon, I wasn't convinced that Milton Wolfe was the one to do it. He struck me as too much of an opportunist and as someone who was too much of a blank slate. I wasn't going to vote against Roberts unless it was for a clear improvement. IMO, Roberts should win the general election.
Thanks for your strong analysis of the KS political picture.