Try history, such as 1992, when Bush drifted left and split the party. Rudy is not a drift leftward for the party, but a lurch.
Meanwhile, those same "meaningless' polls said Republicans will lose both Houses last November, and Republicans did.
I know this can be a difficult concept, but try to grasp it. The closer you get to an election, the more relevance polls have. 22 months is an eternity.