It doesn't surprise me.
Romney does not present much contrast to Obama - and people know this. People are not excited by him. He doesn't give people any really good reasons to vote FOR him, he just serves as the placeholder for voting AGAINST Obama.
But once we leave the cocoon of Free Republic and get out into the real world, as much as many people may not really like Obama all that much, there isn't a sense of "ANYBODY BUT OBAMA!!!!!" that pervades hard-core conservative sites. In short, most people really are not going to be fired up ONLY by the prospect of voting against Obama. Perhaps they should, and many of them will end up doing so, but it's not the psychological attractor for them that it is for FReepers.
Romney just doesn't excite people, since he doesn't present much difference from Obama, other than a few superficialities. Picking a RINO Veep is only going to make that worse. The conservative base has little actual affinity for him, and the independents and the "middle" simply don't see any ideological or practical leadership in the man. People can talk about his "bid'ness experience" all they want, but the fact remains that when you look at Mitt Romney, the average person sees an empty suit with spectacular hair.