From the New York Times on August 4:
“In Gary Johnson’s first run for the presidency in 2012, as the Libertarian Party candidate, he won just under 1 percent of the popular vote. He did not surpass 3 percent in any state.
“That’s not exactly a strong showing. But 2016 could prove more favorable because of the unpopularity of both major party candidates, Hillary Clinton and Donald Trump. Mr. Johnson is at roughly 10 percent in recent polls, well above where he was in 2012. The question, of course, is whether it will have any impact….
“The first debate is scheduled for Sept. 26. If Mr. Johnson can increase his standing in the polls by five points in the next six weeks or so, he could have a major impact on the race. Even if he can’t, there is always the potential for a third party to swing a close election in one candidate’s favor.”