Obama is an easy choice amongst the neo-con, evangelicals we've got in this crop. Romney is moderate enough beyond that, but being a Massachusetts moderate conservative I would have assumed he would be divisive amongst the republican party. This seems to not be the case, as I assume the strategy we are seeing is to use a moderate to appeal to swing voters centrist in their ideologies.
Call me an idiot all you want for voting for Obama, my values split me towards social freedom, over economic freedom, while teetering the razors edge of inconsequentiality since both parties backslide their traditional stances regularly trying to appease whatever demographic of voters needed to get them elected.(example, democrats attacking video games and music as a cheap scapegoat for real problems too complex to boil down into catchphrases, and republicans routinely voting to expand governnent power, think Patriot Act, despite a supposedly "small government" rhetoric)
Scott, Paul's voting record is one of the most consistent in regards to his respect for the constitution. He has made mistakes like all politicians, and he says and supports some things I disagree with. However, he will grab a large group of independents, and many slightly left(such as myself), find him infinitely more electable, and therefore could take a large swath of swing voters.
Lastly, even if Paul gets into office, it is not unlikely his ideas would be diluted, if not wholly suffocated by an increasingly inept, and gridlocked Congress. We have a governmental problem. Not just a Presidential problem.