The cadre of candidate for governor in Washington is only beginning to form, but for years now the single most likely contender – more likely even than the two-term Democratic incumbent, Chris Gregoire – has been the state’s attorney general, Rob McKenna.

Gregoire may or may not run; there’ve been no definitive indicators from her either way, though the majority view seems to weigh against. If she does not, the Democratic contenders seem likely, but not conclusively, to include Representative Jay Inslee and maybe Aaron Reardon, the Snohomish County executive.

Dino Rossi‘s name inevitably gets a mention, but after three straight statewide losses, that seems unlikely. But: AG McKenna seems to have been on a trajectory for this office ever since he was first elected to his current slot in 2004. He has two solid statewide wins to his credit, and unusually for a Republican last time won King County (where he used to serve on the county council). Negatives and criticisms exist (there was a squabble in 2008 over presidential nomination counts), but are not large; he would enter the race with overall strong positives. He does not seem to get into a lot of ideological or philosophical talk; he would not be at all easy to characterize as a right-wing extremist. (That has been one of the Washington Democrats’ strongest weapons against statewide Republicans.) He may be the strongest candidate Washington Republicans have available.

Possibly McKenna’s closest political ally for a decade and more has been Luke Esser, a former state senator. Esser also came from eastern King County (as did Rossi). Although he lost a re-election run in 2006, as Democratic advances moved ahead in that area, he was elected the next year as chair of the state Republican Party, unseating incumbent Diane Tebelius. He was re-elected to the job in 2009. With McKenna on the brink as a strong possibility to run for governor in 2012, and maybe the party’s best shot at the job for a while, Esser’s re-election to the chair would seem to have been assured; he and McKenna could work smoothly together. Gains in the legislature and pickup of a U.S. House seat might not have hurt his case, either.

Except that on Saturday he lost the job, on a strong 69-32 vote, and not just to anyone, but to Kirby Wilbur – one of the last people McKenna probably would have wanted. Like McKenna and Esser, King County knows Wilbur, but knows him as a radio talk show host who talks hard to the right (probably just what appealed to a lot of the central committee members).

Wilbur’s talk show ended in 2009, but he has stayed visible as an occasional fill-in host on Fox for Sean Hannity. That may give you a sense of where he’ll be coming from.

Also this, from a Yakima Herald-Republic blog: “Local Republican activists may remember him from 1992, when Wilbur chaired the State Republican Platform Committee and GOP Convention in Yakima. You may remember that was the state convention when Republicans took philosophical stands against “values clarification, meditation, yoga, homosexuality, divorce, the United Nations, foreign aid, witchcraft and the National Endowment for the Arts.” The platform grew to 18 pages and was emblematic of an ideological fight brewing in the Republican Party over abortion.”

The Seattle Post-Intelligencer offers this: “He will almost certainly move the state GOP further to the right. This weekend showed that McKenna doesn’t control his own party, which is dominated by rural and right-leaning folks who wanted one of their own to direct things heading into the 2012 elections. There’s now a very real possibility that McKenna will face a high-profile opponent from within the GOP (paging Clint Didier).”

If so, he’ll be pressured to move to the right himself, which would give Democrats exactly the opportunity they’ll want in a run against McKenna, and wouldn’t ordinarily get.