This morning, Glenn Greenwald writes:

What happened in this race also gives the lie to the insufferable excuse we’ve been hearing for the last 18 months from countless Obama defenders: namely, if the Senate doesn’t have 60 votes to pass good legislation, it’s not Obama’s fault because he has no leverage over these conservative Senators. It was always obvious what an absurd joke that claim was; the very idea of The Impotent, Helpless President, presiding over a vast government and party apparatus, was laughable. But now, in light of Arkansas, nobody should ever be willing to utter that again with a straight face.

One of those “countless Obama defenders” links is to a post I wrote in 2009, and like any time I get criticized by Greenwald it’s a reminder that he must be an excellent lawyer in a trial situation. But in punditry context I prefer a mode where we attempt to understand what other people are saying rather than a prosecutorial mode. What I wrote, in August of 2009, was that “To get sixty votes you need Ben Nelson or Olympia Snowe to back your bill. Neither Nelson nor Snowe is especially liberal, and the President doesn’t have a great deal of leverage over either of them.” And that’s 100 percent true—in August of 2009, Barack Obama did not have a great deal of leverage over Ben Nelson or Olympia Snowe.

Now what’s the relevance of Arkansas? Well, on March 1 of 2010 Bill Halter launched a primary challenge to Blanche Lincoln. This, as Greenwald explains, gave the White House a great deal of leverage over Lincoln—she needed their active support to beat Halter. Consequently in April when it was widely believed that Lincoln might subvert the White House’s preference for a derivatives title with few loopholes, the Treasury Department fired warning shots in her direction. Soon thereafter, Lincoln took Washington by surprise by unveiling a strong derivatives reform title.

That’s exactly the point I was making back in the summer of 2009. When leverage exists it makes a ton of sense to hold the White House accountable for how they do or don’t use it. In the context of the Lincoln-Halter race, they used it to get their way on derivatives and then they backed Lincoln to the hilt. They could have made different decisions, and if you don’t like those decisions you should feel free to slam them for it. But in the summer of 2009 they didn’t have objective political leverage against Ben Nelson or Olympia Snowe so the progress of health reform was held hostage to their whims. What matters most in politics is the personal predilections of the people who hold office, and what matters second-most is the existence or absence of objective political pressure. Sometimes that pressure exists and sometimes it doesn’t.

In general, the regulatory reform bill that’s already passed the House of Representatives is pretty good. And typically when legislation goes from the House to the Senate it gets less progressive. But one real weak spot of the House bill is its treatment of derivatives, where it sets up a good framework for putting them on a clearinghouse but then ruins it with a proliferation of loopholes and exemptions. The talk out of Chris Dodd has been that he’s aiming for something better, and even Barney Frank (the main author of the House legislation) seems to now see the need for tougher measures.

But for historical reasons (and also because congressional procedure seems designed to make legislation as bad as possible), however, the Finance Committee shares jurisdiction over derivatives regulation with the Agriculture Committee. And there’s been enormous speculation around town that Ag Chair Blanche Lincoln is going to serve up something very weak. The complicating factor, as reported by Benjy Sarlin is that Lincoln is facing a primary challenge from the left from Arkansas Attorney General Bill Halter and he’s eager to make an issue out of this:

Lincoln’s Democratic primary opponent, Bill Halter, is already seizing on financial reform as a potential angle of attack, which could put pressure on the incumbent senator not to stray too far from the administration line.

“As a member of the Agriculture Committee, Senator Lincoln had jurisdiction over derivatives for years but clearly did not do nearly enough to provide appropriate oversight,” Halter said in an e-mailed statement. “I support the strongest possible financial reform bringing more accountability to our financial markets so that another financial meltdown doesn’t happen. The reforms in Senator Dodd’s bill should be seen as a floor, not a ceiling.”

Obviously members from more conservative states are going to need to be more conservative on certain issues. But I’m hard-pressed to imagine that the voters of Arkansas are demanding loopholes in derivatives regulation.

Blanche Lincoln is sufficiently to the right of most congressional Democrats that it’s easy to imagine she’s someone it’d be easy to mount a primary challenge to. And certainly with Lieutenant Governor Bill Halter securing a large financial commitment from the AFL-CIO, he’s got a decent shot. But Tom Schaller points out that Arkansas isn’t just more conservative than the rest of America, it has a much more conservative group of self-identified Democrats:

It’s also not clear that there’s that much room to run to Lincoln’s left in Arkansas, which has one of the more conservative sets of Democratic primary electorates in the country — only 36 percent of Democratic primary voters identified as liberal (and 12 percent as very liberal) in 2008, according to exit polls. Along the same lines, while 25 percent of Arkansas Democrats say that Lincoln is too conservative, 18 percent think she’s too liberal. Halter can perhaps win just by being fresher/different/”better”, but there’s not likely to be the appetite in Arkansas — even among the Democratic primary electorate — for a mere Southern-fried coastal liberal.

What’s more, both Lincoln and Halter are looking doomed in the general election. In Presidential politics, Arkansas has become a very conservative state—Obama got 38.9 percent of the vote compared to 52.9 percent nationwide—and you have fewer people inclined to ticket-split these days than you did in the past.