Solid move or Hail Mary? On the one hand, McCain is an iconic opponent of pork-barrel spending – one of the most important issues in the House leadership race. On the other, McCain is unpopular among many conservative House Republicans because of his positions on climate change and campaign-finance regulation. Also, there is the issue of whether McCain, a Senator, is sticking his nose in where it doesn’t belong.

At a press conference today, McCain addressed that last concern thusly: “I think it’s appropriate given the tenor of the times, because any reforms that are going to be enacted have to be enacted on a bicameral basis.” McCain also confirmed that he is making phone calls for Shadegg.

One reporter asked Shadegg whether he shared McCain’s views on climate change. He said that he and McCain have “very intense and differing views” on many issues (“Not too many,” McCain interjected), and that climate change is one of them. Shadegg said some of the evidence for human involvement in climate change is sound and some the evidence is unsound.

I asked Shadegg if he agreed with McCain (and Roy Blunt, for that matter), that campaign-finance regulation should be extended to cover the political activities of 527 organizations, or if this is another issue where he and McCain have “very intense and differing views.” He said, “I had different views from Senator McCain’s on campaign-finance reform to begin with, but I feel strongly about applying the rules evenly, and I think they’re not being applied evenly to 527s… I think the ability of 527s to spend vast and unaccounted sums of money behind the scenes where the public doesn’t know about it is a serious problem, and I think Senator McCain agrees with that, and I certainly agree. And we need to do something about that.”

In some ways, McCain and Shadegg make a natural alliance – both represent Arizona and both are outspoken advocates of government spending reform. The trick for Shadegg will be avoiding the negative associations among conservatives that come with an endorsement from John McCain.