Rob Johnson, executive director of the Transportation Choices Coalition and the star of several of Mayor Greg Nickels' campaign videos, has endorsed mayoral candidate Mike McGinn, according to McGinn's Facebook page . (Facebook pages, as everyone knows, being the arbiters of truth in these modern times). Nickels lost to McGinn and Joe Mallahan in last month's primary. Johnson's endorsement of McGinn was far from certain—as recently as last week, McGinn had not directly contacted Johnson seeking his endorsement since the primary (he did run into Johnson in the street and ask him to sit down for a beer), and insiders speculated that Johnson would not throw his support behind the combative Nickels challenger.

The Transportation Choices Coalition (and Johnson personally) clashed with McGinn in 2007, when the two were on opposite sides of the frequently ugly debate over the roads and transit ballot measure (Johnson and TCC supported it, McGinn and the Sierra Club, which he used to chair, did not). The view of many insiders was that there was no love lost between the two men, whose styles—Johnson is collaborative, McGinn combative—couldn't be more different.

Update: Johnson confirms that he has endorsed McGinn. "We had a nice, long conversation last night and at the the end of that conversation I said, 'Count me in,'" Johnson says. "I think that McGinn has a strong vision for the city that aligns well with a lot of our priorities."