Maine:

Arkansas:

Missouri:

Indiana:

Lots of folks have taken note of new polling today showing John McCain potentially in trouble in next year’s Arizona Republican primary for his Senate seat.

Matt Yglesias flags an important aspect of this:

This seems like pretty much terrible news for the world. The most likely path between Point A and Senate passage of a reasonable climate bill is for McCain to rediscover his interest in the issue. But that’s not the sort of thing a Senator worried about a right-wing primary challenge is likely to do.

This is exactly right. And of course, a Politico story (where else?) provides the evidence:

Sens. Lindsey Graham and Joe Lieberman have been working overtime to craft a climate bill that can attract significant GOP support. But they aren’t exactly scoring points with their mutual best friend in the Senate, John McCain. “Their start has been horrendous,” McCain said Thursday. “Obviously, they’re going nowhere.”

This should not be a surprise for anyone who has been paying attention to McCain’s statements on climate legislation since last year’s election.

Steve Benen checked in with a McCain spokesperson on this and got an absurd response:

Asked for an explanation, McCain spokesperson Brooke Buchanan said, “This really hasn’t been done in a bipartisan fashion.”

I see. The climate bill is being pushed by a Dem (Kerry), a Republican (Graham), and an Independent (Lieberman), but the problem is that the effort is too partisan. Follow-up question for Brooke Buchanan: “Huh?”

Predictably, arbiter of conservative-leaning beltway conventional wisdom Chuck Todd blames President Obama for not reaching out enough.

There is a larger point to all of this though. Primary challenges are an extremely effective way to hold ‘moderate’ Members of Congress to the party line. Probably the single most effective way to do so, I’d say.

Arlen Specter is a great example of this (full disclosure: I can’t stand Arlen Specter):

Specter’s overall party loyalty score since becoming a Democrat — counting votes both before and after the primary challenge — is 87 percent. This contrasts with the 44 percent of the time that he broke ranks to side with the Democratic on Contentious Votes while still a member of the Republican Party. He’s basically been behaving like a mainline, liberal Democrat.

On the other hand, it’s hard not to imagine that this process has been strengthened, accentuated, catalyzed, by Joe Sestak’s primary challenge. You can draw a pretty clear line in the sand from when Specter went from sorta, kinda Democrat to OMG totally! Democrat, and it coincides with the date that Sestak announced his challenge.

Continuing this trend, Specter called for an exit strategy in Afghanistan just yesterday.

This chart couldn’t make the Specter example any clearer:

The obvious lesson here is that Democrats should mount aggressive primary challenges against Democrats who are getting in the way of healthcare reform, clean energy legislation, the employee free choice act and job-creating stimulus provisions. Defenders of the status quo will maintain that this tactic is more effective in places like Pennsylvania than it would be in places like Nebraska, Arkansas, Indiana or Louisiana, and they are probably right. But the way we deal with such Senators now doesn’t seem to be working very well, so I’d be more than willing to give this other strategy a shot.

Via Grist:

Thank you for contacting me regarding the impacts of global climate change. I appreciate your thoughts and concerns on this issue.I am deeply concerned about the threat posed by global climate change. The scientific consensus on this issue is unequivocal. Global warming is real and greenhouse gas emissions from human activity are causing it. Scientists and others warn that climate change threatens our nation’s security, and may imperil future generations’ opportunity for safe, healthy, and prosperous lives.

However, any carbon-constraining mechanism must protect Hoosier ratepayers, workers and businesses from increased costs. Additionally, other nations of the world must be included in this effort, because if they are not, our action will be for naught.

Please rest assured, should legislation regarding global climate change be introduced in the 111th Congress, I will keep your views in mind.

Again, thank you for contacting me. I hope the information I have provided is helpful. My website, http://bayh.senate.gov, can provide additional details about legislation and state projects, and you can also sign up to receive my monthly e-newsletter, The Bayh Bulletin, by clicking on the link at the top of my homepage. I value your input and hope you will continue to keep me informed of the issues important to you.