One of the more notable Sunday show interviews featured some pointed, refreshingly candid criticisms of the Republican presidential field. The notable part was the person making the criticisms.

The guest, reflecting on Mitt Romney’s flip-flops, told ABC, “If we talk about inconsistencies and change on various issues, we’d be here all afternoon.” Referencing the GOP’s top tier, he added, “I think when you find yourself at an extreme end of the Republican Party, you make yourself unelectable.” He slammed Rick Perry on secession; he slammed Michele Bachmann for policy ideas that are “not founded in reality; and in light of the debt-ceiling fight, he said he “wouldn’t necessarily trust” the Republican presidential field on economic affairs — a field with candidate who’ve offered “no substance” on the campaign trail.

Of course, the guest was former Utah Gov. Jon Huntsman, the former Obama administration official running for president as a Republican. As we discussed yesterday, Huntsman has nothing left to lose — he’s running last and seems to have no credible chance of winning — which frees him to speak his mind.

Democrats are thrilled.

Jon Huntsman’s appearance on ABC’s “This Week,” is winning applause from one of the two major political parties. It’s not the one Huntsman’s hoping to represent as its nominee for president. The Democratic National Committee just blasted out a greatest-hits reel from Huntsman’s Sunday show appearance, wherein the former Utah governor criticized Rick Perry for being anti-science, Michele Bachmann for being unserious about the economy and Mitt Romney for being a flip-flopper. The DNC subject line: “Don’t take our word for it …”

Nothing says “credible Republican presidential candidate” like having the DNC trumpet his on-air comments.

In fairness to Huntsman, he slammed President Obama — a man Huntsman once described as an “extraordinary leader” — during the interview, too. The criticisms were weak and kind of silly — he said Obama could have resolved the GOP’s debt-ceiling fiasco by “walking away from the teleprompter,” which is pretty foolish — but Huntsman didn’t just attack his GOP rivals.

But his willingness to blast his party stood out, in large part because we just don’t hear Republicans speaking this way very often.