0.5% - 1.0% The libertarian party has only done better than 1% once and this is not the year, nor is Johnson the Candidate who can duplicate that feat.
Johnson is a good candidate and this seems to be a year where third parties could overperform...
1-1.5%. God, why didn't he run for the Senate?
Exceeding 1.0% would require Johnson to do more than twice as well as any Libertarian candidate has done since 1980 when Clark/Koch hit 1.06%. It's just not gonna happen folks, not unless Romney or Obama implodes so that people don't mind casting a wasted ballot.