Tonight was Mitt Romney’s last stand. He blew it. The conservative antipathy towards McCain involves real issues: his indefensible support of campaign finance reform, his opposition to Bush tax cuts, his throwaway lines attacking corporations, and so on. Romney should have been on attack mode from the first moment, stirring up every conservative trepidation about McCain, stressing his unreliability as a consistent voice for the cause. “We don’t need a maverick, Senator, we need a steadfast, principled and predictable conservative leader,” was the line I was waiting for. Instead, Romney dove head-first into McCain’s alleged smear about who supported the surge — a minor kerfuffle given all the other heat McCain has taken these last few months.

Why, for example, didn’t Romney simply quote George Will,Rush Limbaugh, Sean Hannity or any other of the pantheon of conservative pundits who don’t trust McCain?

Romney’s most credible claim is that he understands the real economy and can speak about it eloquently. California is Proposition 13 territory, after all. His entire campaign was premised on his free-market bona fides. Tonight, when he needed them most, he barely displayed them. In New Hampshire, McCain made Iraq the touchstone of campaign. He did it again tonight and Romney let him get away with it. This contest seems very over.