Your comments thus far don't quite reflect awareness of what's going on with the Manilow donation, though it would seem to be obvious. Ron Paul is most assuredly not the "favorite candidate" on any leftist, anti-war nutball, nor is he deliberately seeking support from that quarter. However, some of those people seem to think that throwing some money at his campaign is a worthwhile investment. By doing so, they help keep Paul's campaign afloat and hopefully, cause some trouble for the Republican candidates that they *really* dislike.
Remember too, that the war is absolutely central to the left's hatred of Bush, so any Republican who makes ending the war a large part of their campaign will be smiled upon by the libs. The question then becomes: Is Ron Paul seen by the left as an acceptable worst-case-scenario alternative? We'll find out in the open primary states, just wait.
Please explain to me why would liberals support Paul in the primaries? He's virtually the only candidate who can pull a coalition of voters together like Reagan did in 1980. If he's nominated, the Dims will lose a good third of their voting base (young adults, single professionals, Reagan Democrats fed up with Bush, etc) right there.
Except for withdrawing from Iraq (and even then, his reasons for withdrawing is not similar to the liberals' reasons), Paul has nothing in common with liberals or liberalism. He wouldn't use troops to help the Left's favorite humanitarian causes. He supports limiting the federal government and is pro-life.