From early on, the Alaskan Way viaduct – or rather, whatever will replace it – has seemed to be at the core of the Seattle mayoral race. Now there doesn’t seem much doubt.

Headlines last week seemed to raise the image of incumbent and outgoing Mayor Greg Nickels poised to push the tunnel project – backed by one mayoral runoff candidate, Joe Mallahan, and opposed by the other, Mike McGinn – as far as he could, maybe to a point of no return, before he leaves office. Nickels has held off on some other things in favor of his successor, but this . . . this would be a big one.

And McGinn is pouncing. He points out that the city’s share of the tunnel cost is $930 million, and he’s very pointedly asking Mallahan where the money will come from.

In this, there’s some positioning. Both McGinn and Mallahan are Democrats with ties to various parts of the city’s Democratic infrastructure. So check out McGinn’s current front page on his web site: The lead item is about the “Battle for Seattle,” a fundraiser, and goes on: “The Battle for Seattle (and King County). A joint benefit for Mike McGinn, Dow Constantine, and Pete Holmes. With music from The Presidents of the United States of America featuring Krist Novoselic.” Constantine, recall, is running for (the nonpartisan office of) King County executive; he is a Democrat, and his opponent is widely perceived (or often described at any rate) as a relatively conservative Republican.

Getting the picture of how the framework is intended to be set up?