Barone is pretty balanced in his analysis. I have disagreed with him many times, but he is usually right.
He went through this on Hannity Friday on air. Not only state by state, but he explained within every state and certain key precints, local issues, etc which led him to his prediction. Frankly, I was amazed at his knowledge at the state level.
Another thing to consider... a vast majority of the media that is closely covering the election have inside information. The reporters who travel with the candidates have info leaked off the record every day. They have a pretty good sense of what the campaigns know. Barone is very connected and probably has some inside information, which is making him more confident.
Rove, Morris, Barone and others are now predicting a Romney win. None of them predicted a McCain win in 2008.
Krauthammer on O’Reilly last night predicted an extremely close Romney win, within .5% popular vote and a handful of EVs.