If there was any doubt left that Newt Gingrich’s much-vaunted positive campaign was deader than New Coke, the candidate removed it on Tuesday night with a speech lashing out at two of his top rivals.

Without naming Mitt Romney, whose campaign and its allies pelted Gingrich with attack ads all month, Gingrich condemned an “avalanche of negative ads” that left him “drowning in negativity” and contrasted Santorum’s “great positive campaign” with his, again unnamed, rivals.

As for top-three finisher Ron Paul, Gingrich described his views as “stunningly dangerous” before describing a grotesque image of a suicide bomber detonating his weapon to make his point that Paul was insufficiently concerned about Iran’s nuclear program.

Gingrich made clear on Wednesday that his campaign would be on offense soon, telling MSNBC that “we’re going to be defining Romney out of the mainstream of the Republican party.” His campaign has already sought to paint him as a “Massachusetts moderate” in press releases and public events.

He had said earlier in the week that Romney “would buy the election if he could” and accused his rival of being a “liar” by distancing himself from independent attack ads against him.

Ironically, a Super PAC set up by one of Gingrich’s longtime aides, Rick Tyler, is preparing to do exactly the same thing in South Carolina and possibly New Hampshire, announcing plans on Tuesday to “define” Romney in new ads. Gingrich has said in the past he would condemn such behavior from groups that support his candidacy.

Benjy Sarlin

Benjy Sarlin is a reporter for Talking Points Memo and co-writes the campaign blog, TPM2012. He previously reported for The Daily Beast/Newsweek as their Washington Correspondent and covered local politics for the New York Sun.