BACK on the campaign trail, Gary Johnson cuts a slightly disconsolate figure. Appearing in a sports bar in the town of Gallup, New Mexico, the former Republican governor, serial presidential hopeful and now Libertarian Party candidate for the Senate, spoke unenergetically about what he would do there. He would fight the deficit, be bipartisan, facilitate whistle-blowing on government waste, he said, with lengthening pauses between each item. After ten minutes, a puzzled look crossed his face and Mr Johnson fell silent. An aide suggested that the small crowd should mingle with him instead.

Lexington later put it to Mr Johnson that he seemed to dislike campaigning. He nodded. “The bad part is you find yourself with people that have really bad breath,” he said. “What comes out of their mouth is just as bad. You cannot make heads or tails out of what the person talking to you is even saying.” Mr Johnson is many things: a wealthy builder, ultra-marathon runner, fiscal hawk and pothead. He is not much of a retail politician.

He could still be competitive in a race the Democrats were assumed to have sewn up. A recent poll puts him in second place to the Democratic incumbent, Martin Heinrich, with 30% of voters undecided. Mr Johnson is remembered in New Mexico as a frugal and fairly effective governor. After his presidential run in 2016, also as a Libertarian, he is known nationally for his goofball manner, indifference to world affairs and dope habit. Yet he may be the most prominent advocate of libertarian principles left standing. That illustrates how badly the ideology has recently fared.

Only a tiny minority of Americans are ideological in any way, and the number of committed libertarians is a rounding error. Most of those who voted for Mr Johnson in 2016 were protesting against the alternatives. Yet a clutch of liberty-minded Republican mega-donors have made their views prominent on the right. Led by the industrialists Charles and David Koch, they have sponsored free-market think-tanks and policies, on immigration reform as well as tax cuts, which liberty-inclined conservatives such as Ted Cruz and Marco Rubio have sometimes taken up. Most Republican voters are more drawn to the party’s social conservatism. Yet in the Koch-supported Tea Party revolt of 2010, ostensibly against government spending, some saw an army of liberty-minded voters awaken at last. How wrong they were.

Tea Partiers love Mr Trump, who seems to have zero regard for liberty. Their revolt, it turns out, was not just against spending. It was also against immigrants and poor people and the vast handouts they imagined these scapegoats received. The populist libertarian strain—represented in the 1990s by Ron Paul, another serial presidential candidate—has long been infused with racial anxiety. It also contains a lot of anti-government paranoia, which explains why Mr Paul’s followers—including his son, Senator Rand Paul—are suckers for Mr Trump’s deep-state conspiracy theories.

Thomas Massie, a libertarian-ish congressman, has admitted to revising his view of his supporters. “After some soul-searching, I realised when they voted for Rand and Ron and me in these primaries, they weren’t voting for libertarian ideas—they were voting for the craziest son of a bitch in the race.” While Mr Trump has blown up the deficit, raised barriers to trade and immigration, threatened civil liberties and states’ rights, and put former lobbyists in charge of deregulation, Mr Paul, a self-described libertarian conservative, has been one of his staunchest allies.

The mega-donors have not done much better. Contrary to excited media reports, Charles Koch, who now runs the brothers’ network, has not rethought its backing for a Republican Party that appears no longer even to support free trade. Its members, who have profited hugely from Mr Trump’s tax cuts and deregulation, are expected to spend $400m on Republican campaigns over the mid-terms. Democrats have long claimed that Republicans’ harping on liberty was a pretext for lower taxes for the rich and fewer food stamps for the poor and curbs on pollution. That used to be an exaggeration. But the Trump party and its wealthy abettors appear to be proving their most partisan critics right.

All ideologies are vulnerable to opportunists, but the purity demanded by libertarian conservatives has made theirs especially susceptible. Unthinking anti-government rhetoric has precluded serious new thought about the relationship between government and individuals in an anthropogenic climate, changing economy and more atomised and diverse society. Moderate conservatives often have more nuanced ideas. They typically want a more efficient, but not radically smaller, government. They might even expand it sometimes, to combat obesity or global warming. They are also increasingly repelled by strident social conservatism: they may oppose abortion, but they are relaxed about gay marriage. They are arguably the most sincerely liberty-minded group of Americans. Yet the Republicans, who claim to stand for liberty, are driving them away. The party will not win national elections unless it can win them back.

Equality and fraternity also matter

If Mr Johnson’s campaign takes off, it could also illustrate how that might be done. Because, in a state that leans Democratic, he must borrow Republican voters, then add moderate Democrats, a group that also worries about liberty out West. Mr Johnson’s pragmatism should help him. He tends to argue for libertarian policies on the basis of economic sense, not ideology. He says he wants to legalise his favourite drug because it would create thousands of jobs, not because it would make Americans freer.

His injudicious comments on halitosis aside, he also avoids attacking others, including his rivals, whom he scarcely mentions. That is amiable as well as ideologically sound, and liable to be effective. Some libertarians dare to hope that, in response to Mr Trump, Americans will start demanding more liberty from their leaders. But many of them would settle for more civility.