THE Colorado Republican party’s nightmare is coming true. Tom Tancredo, unfazed by the three so far ineffectual candidates running against him, is speeding toward victory in the GOP primary race for governor. Tancredo is a controversial national figure known mostly for his fiery, unswerving position on illegal immigration — which he sees as a plague that officeholders on every level of government must address as a top priority. Tancredo is an avuncular character with a hard edge. He is in the moment on the stump and in intreviews, quick with a joke, ready to spin out stories and asides that...