Last week, Harry Reid and Mitch McConnell got into an argument on the Senate floor about which party has been primarily responsible for Senate gridlock. Reid cited Norm Ornstein and Tom Mann, the two centrist, non-partisan political scientists who blame Republicans for unprecedented obstruction in their current book, It’s Even Worse Than It Looks .

McConnell didn’t have much of a substantive response, but instead went ad hominem, calling them “ultra, ultra liberal.”

Well, today Ornstein fired back in his Roll Call column.

Ornstein deployed a half-dozen or so quotations from McConnell himself in which the Minority Leader bragged about how his goal since January 2009 has been gridlock and the denial of a second term for Obama. Ornstein also detailed all the ways McConnell has ground the workings of the Senate to a halt.

Which is really what you need to know as far as responsibility for gridlock is concerned. Throughout Barack Obama’s presidency, one party wanted to get things done and the other didn’t. One party, especially in the current Congress, wanted to cut deals and find workable compromises, while the other party has been against compromise on principle — and what they believe is politically necessity.

Remember: Republican Senator Bob Bennett wasn’t denied renomination because he was actually liberal on issues. He was defeated by Tea Party Republicans because he was open to cutting deals. Right now in Texas, a high-priced Senate primary is about to result in a win for a previously obscure conservative over the Texas Lieutenant Governor on basically one issue: the willingness to compromise with Democrats.

The answer to this is clear: As Ornstein says, gridlock in the Senate is happening, with record numbers of filibusters and unprecedented other forms of obstruction, for really only one reason: because Mitch McConnell and the Republicans want gridlock.

Verdict? TKO, Norm Ornstein.