Leave it to the Republican Governors Association to let Jared Polis know that fellow Democratic gubernatorial candidate Mike Johnston isn’t impressed with the ability of the liberal congressman from Boulder to work with Republicans. (Say it ain’t so!)

The RGA released a poorly shot video of a Johnston speech Thursday morning. Poorly shot is usually a sign of something clandestine and worth a reporter’s time. Not so much this time.

“I think what I do know is that the people who have been the most effective in governing this state look like the folks seated in this room,” Johnston told the small crowd. “If you were to ask Republicans if they had to work with one Democrat, in the House, who would it be – they would say (state Rep.) Millie Hamner and that’s not always because she’s going to agree with them, but she’s always going to be honest, always going to reach out, and find ways to collaborate that people don’t always do.

“And I think when you have to govern a state that is a third Republican, a third Independent and a third Democrat, you have to do that. I don’t think Jared has had to do that in his role as much as a congressperson, because they don’t get as much done there.”

What? That’s it? The RGA promised “attacks” in the subject line of an e-mail to the state’s political reporters.

“With Colorado’s Democrat primary quickly shaping up to be an ugly contest between two unapologetically far-left candidates, the race between Johnston and Polis will continue to divide Democrats, leaving their party less likely to emerge victorious at the ballot box on Election Day in 2018.”

It’s an increasingly crowded field, and it’s not clear yet that Polis or Johnston is the front-runner. Lt. Gov. Donna Lynne announced this week she’s forming an exploratory committee, which would shake up the race.

That’s ugly? One thinks the RGA’s tracker (or the RGA) started in politics this week. As attacks go, the RGA is reaching from the moon to Mars on this one, and if this is as good as they can get, it might speak to a very cordial Democratic primary.

What must the RGA think of GOP gubernatorial candidate Victor Mitchell calling out fellow GOP candidate Doug Robinson last week for donations he received from Utah, including from Robinson’s uncle, Mitt Romney.

“Colorado is in a fierce competition for jobs and investment, and one of our key regional challengers is the state of Utah,” Mitchell told Colorado Politics’ Ernest Luning. “A candidate who is so reliant on donors from that state couldn’t possibly avoid conflicts and uncompromisingly lead Colorado to win any and all economic development battles with Utah.”

Replied Robinson: “It seems like Victor has taken Gov. (John) Hickenlooper’s recent lesson in political grandstanding to heart.”