It does not seem that it should be the case, but the Ron Paul candidacy is actually causing more than a little dissent within libertarian circles. There are more than a few who are not only displeased, but actually oppose his candidacy.
Some, like Classically Liberal Student over at the Classically Liberal Blog do not care for Representative Paul because of an opinion that he is not libertarian enough to warrant support. Although one can disagree with his analysis, it is still a consistent and supportable position to take. And CLS backs up his opinion with very well thought out arguments. This does not mean to say that CLS is a purist, and he has said he is not, it is just that his arguments are that Representative Paul is not sufficiently libertarian on enough issues, and he has taken the time to highlight those issues to present a compelling argument.
But in general it appears that the more radical libertarians are more eager to support Representative Paul, while those in the so-called "reform caucus" seem to be the most opposed to his candidacy. The Facebook group "Stop Ron Paul 2012" which recently became famous for a proposed false flag attack involving members dressing in Klan robes, was founded by a member of the Libertarian Party.
And outside the Libertarian Party, there are others who claim allegiance to the ideas of liberty in a much less radical fashion than the Libertarian Party’s version, such as the Republican Liberty Caucus; after that caucus endorsed Ron Paul the Vice Chair Aaron Bitterman resigned in protest. The Republican Liberty Caucus had been doing nothing for years, but then Ron Paul's 2008 campaign led to an infusion of new and energetic people that revitalized the caucus in spite of the leadership. Then, of course, there is former staffer Eric Dondero who has spent years opposing Ron Paul and claims to be libertarian.
If an argument can be made that Paul isn't libertarian enough for purists, the Reform Caucus should be the most welcoming of Representative Paul. But it seems the radicals are more likely to be friendly to Paul and instead it seems that for more than a few on the reform side he causes them problems. So what about his campaign causes reformers problems? Taking them at their word, he is supposedly an opponent of Israel and isn’t eager enough to use the military to attack Iran.
He takes the most consistently libertarian position possible on foreign affairs; peaceful relations with all, entangling alliances with none. While he doesn't blame the United States for everything, he does blame the United States for the things that the United States is responsible for. He doesn't believe it is the job of the American Tax Payer to pay for the defense of other countries.
Some on the less pure side of the libertarian spectrum have convinced themselves that the job of the United States military is to force people in other countries to be free. The most well known politician with genuine libertarian leanings is, leaving aside any question on purity on other issues, taking the purist radical libertarian position on foreign affairs. He is putting to lie their arguments, exposing their own departures from libertarian thought.
Since he would not give foreign aid to any country, that means he would not give foreign aid to one country in particular. His statements are then taken out of context to show opposition to that one country in particular, and he is called an anti-Semite as a result. His refusal to help any country is portrayed as a hostility to that one country, and then reinterpreted as a support for that country’s enemies.
The arguments used are identical to the arguments these same people oppose when progressives try to accuse libertarians of racism. Exactly like how a progressive starts with "that person disagrees with me" and ends with "that person must be a racist" these anti-Paul libertarians start with "I don't like Ron Paul" and end with "he must be an anti-Semite" or "he must be a racist." The evidence simply doesn't support such a conclusion.
It is pretty obvious what causes progressives to have problems with Representative Paul. He causes them to have to evaluate what it is they really believe in, and they don't like what he reveals to them about themselves. It is also pretty obvious what causes conservatives to have problems with Representative Paul. He causes them to evaluate what it is they really believe in, and they don't like what he reveals to them about themselves. The same is true about these libertarians against Ron Paul.