If there’s an opportunity for Johnson to make a difference anywhere, it’s likely in Mountain states such as his native New Mexico, and Colorado and Nevada, where he could shave votes from the major-party candidates. In a close race that neither side thinks will be an electoral landslide, Johnson could make a real difference — especially with Ron Paul’s libertarian-leaning backers now up for grabs.

“The people who are saying they’re going vote for Johnson right now generally are people who dislike both Obama and Romney,” said Tom Jensen, of the Democratic firm Public Policy Polling, which has found Johnson polling between 5 percent and 10 percent in some states.

Those numbers will eventually fall back to earth, Jensen predicted: “I’m just relying on history on that front — unless a third-party candidate’s really well-funded and getting visibility similar to the others that they’re facing [they fade]. Most of these people who are saying they’re voting for Gary Johnson right now will end up voting for Romney.”

Johnson doesn’t see himself as a receptacle for protest votes.