At first blush, the proceedings on the Senate floor yesterday afternoon may have seemed rather routine. Sen. Tom Coburn (R-Okla.) pushed a measure to end nearly $6 billion a year in tax subsidies for ethanol, and as expected, the effort came up far short. Coburn’s proposal needed 60 votes, and it got 40.

But there’s a much larger significance to this that’s worth appreciating. Under the rules of Republican politics, as dictated by Grover Norquist and his anti-tax “pledge,” voting to end industry tax subsidies counts as support for a tax increase — a step GOP lawmakers are supposed to never take under any circumstances. And yet, yesterday, 34 Republicans voted to cut ethanol breaks anyway.

Ryan Grim and Elise Foley said the move “is likely to have significant repercussions on the debate over spending, revenue and the federal deficit.”

[T]he break with [Norquist] has major implications for the debt ceiling negotiations going on just off the Senate floor Tuesday with Vice President Joe Biden. Republicans are insisting that any measure that increases revenue be off the table. But ending ethanol subsidies is a way of increasing revenue….

As we’ve discussed many times, some Republicans are willing to parse the meaning of the word “revenue.” GOP officials are demanding a deal to address the debt they created, and they’re demanding that tax rates remain exactly as they are now. But many Republicans haven’t ruled out the possibility of additional revenue as part of a compromise, and the notion of ending some subsidies is on the table. Uber-activist Norquist thinks it counts as a tax increase, but the GOP increasingly disagrees, which is evidence of at least some progress.

And if Republicans accept additional revenue as part of a debt-reduction deal, the likelihood of a less-insane compromise increases. The more the GOP stops taking orders from Norquist and his ilk, the more constructive the process becomes.

So, that’s the good news. The bad news is, it only looks like good news because the radicalism of the Republican position has become so commonplace. As Ezra noted this morning, “Instead of revenues being an assumed part of a deficit deal, with the only question being how much of the deal they make up, the question has become whether Republicans will accept any revenues at all in the deficit deal. Including any new revenues at all has been framed as a major concession for the Republicans, which means it’s easier for Republicans to include far less revenue in total. And no matter how you look at it, that’s a win for Grover Norquist.”

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.