That even a lefty understands that there aren’t many candidates who are actually credible as Candidates is not the same as them WANTING those candidates.
Perry’s biggest selling point is that he IS a credible candidate for the Presidency, whether you want him to be president or not. Romney isn’t nearly as credible as a candidate, having nothing more than 4 years as a governor of a small liberal state. They can joke about Roemer, but he has more experience in leadership than Romney does.
Pawlenty was another candidate who was a credible candidate. Totally uninteresting to the voters, so he dropped out. But credible.
I still think there is a solid subset of the left that is upset that Cain seems to have been derailed. There was no indication from the left that they were targetting him, until Politico ran their one story and a minor matter got blown up into a multi-week allegation-fest.
And I’m still not convinced Gingrich is a credible candidate. He’s a great debater, and smart as a whip. But I do think once everybody remembers everything about Gingrich, they won’t be as excited by him.