If we don't support Liberty (both Ron Paul and Gary Johnson), Johnson will not be included in the debates, his presence and the voice of Liberty will not wake up any more people, he will not increase our numbers, and real polling data come November will probably look like this: Johnson 5% Romney 44% Obama 44% Other 7%. I'll write-in Ron Paul, of course, and since he is not on the actual ballot, he will be grouped into the "other" category and that's that. I stuck to my principles.
However, if we support Paul and Johnson, Johnson could be included in the debates, he could help wake up even more people (especially the Democrats who didn't pay attention to Paul because of his brand Republican), he could grow our numbers to new heights, and real polling data could like this: Johnson 31% Romney 31% Obama 31% Other 7%. I believe Liberty is that popular, do you? In this case, I'd definitely vote Gary Johnson instead of writing in Ron Paul. Wouldn't you?