A lot of the accomplishments listed on his website (link above) tout that he was a principled conservative in the face of Democratic majorities and that he continued to hold those principles dear throughout his tenure. More than likely there was a bit of compromise involved and there's nothing wrong with that (unless you are trying to get the GOP nomination.)
Normally, I'd go through the poll numbers, attempting to read the tea leaves about what the latest batch means for one contender or another, how the affect of a primary or caucus will play out on a particular candidate. The unfortunate truth of the matter is that Gary Johnson doesn't appear in any of them. This either means that his name isn't mentioned by the pollsters (and if they are, people don't know or support him) or if the pollsters are asking for candidates that the voter supports, they still don't mention this to him.
Is the media to blame for this? Yes and no. The media has had an insatiable appetite for GOP candidates. The moment that Rick Perry entered the race, they were already looking at each other with wide eyes and salivating mouths wondering if Rep. Paul Ryan was going to enter the race. Rudy Giuliani is still floated as a possible entrant into the competition and almost any other Republican that has a modicum of respect in the party or one that has conservative appeal is mentioned (Sen. Marco Rubio.)
At the same time, however, Johnson has done little or nothing to stand out as a candidate in the current field. He can give great answers to debate questions, his appeal is good (not great) and his character is without question. But when you got a crazy lady like Rep. Michele Bachmann running for president, how's a reasonable guy supposed to get any respect around here? He's a little to the left of someone like, say Ron Paul, but Johnson still believes that the drug war is bullshit and that the government shouldn't spend the kind of money on it that it has been spending. And what does that get you? Well, ask Ron Paul.
In the research that I've done for Gary Johnson, the fact of the matter is that wherever he is, he's starting from square one. He declared that he was running back in April of this year but if had waited until last month, it would have been better for him. He would have entered the race and there would have been a flurry of media attention and speculation. With that, he could have established himself as candidate to be dealt with, got his message out and thereby establishing a foothold in any of the states.
So what are the odds that Johnson is going to make headway? Well, a few of the candidates are going to have to drop out. Not the top tier, mind you, but the lower tier. Santorum, Gingrich and Cain would have to quit the race and Johnson would have to stick around (I don't know what would cause them to drop out, but this is a hypothetical, right?) Then, by being the only bottom tier candidate that is still sticking around, he would get more attention not just from the media but from anybody. The Campaign That Lived, kind of thing.
If Johnson survives to the actual primary season, he could do well in NH and NV, but he would get decimated in IA and SC (where religion and social issues are more important. Johnson himself just made a blog post about how social issues were not going to win the White House. By the way, somebody should tell Santorum that.)
I'm not writing the campaign obituary yet because, again, anything can happen in the campaign, but the chances are beyond dim, they're just plain dark.
You can follow me on Twitter where I actually have more positive things to say than this @truthissoap