after all, only the most whacked out Tea Partiers are against government funding of roads (which is actually a problem in Virginia - where the old-time business Republicans are having a hard time getting road funding).
I think it comes from the Republican think tanks of the 80s, where they tried to remake America into Republican voters - which is where the 401K came into being. Note that Republican voters tend to be suburban and rural - so, rail makes more dense, urban living possible and must be defeated at all costs.