THIS is a humbling election season for folk who think they understand American politics. A rather hangdog mood duly hung in the air at the second Republican presidential debate on September 16th, hosted by the Reagan Library in southern California. The assembled strategists, spin doctors and journalists watched the field of 15 candidates variously flub their lines or deliver zingers and, as is conventional on these occasions, tentatively drew up rankings of winners and losers.

By conventional rules, the season’s shock front-runner, Donald Trump, had an iffy night. After months of climbing in the polls with a mixture of boasting, bigotry and abuse for rivals—a style The Donald referred to on debate night as “braggadocious”—he was floored by a withering put-down from Carly Fiorina, a former technology chief executive whose looks he had earlier slighted. Ms Fiorina, who used to run Hewlett-Packard, a computer firm, swatted aside Mr Trump’s claims that he had not meant to insult her with a brisk: “I think women all over this country heard very clearly what Mr Trump said.” The billionaire property tycoon blushed a crimson red, and stammered that he thought Ms Fiorina “beautiful.”

Jeb Bush, a former governor of Florida who was once expected to be dominating the contest by this point in the cycle, also had a so-so evening. Mr Bush landed a couple of blows, but could not shake his habit of lapsing into wonkish jargon. A low point came during a long and emotional discussion of abortion, when Mr Bush (a devout Catholic) vowed to cut federal funding for abortion providers by restoring a Reagan-era legal interpretation of a budget line he named as “Title X of the HHS funding”. Senator Marco Rubio of Florida had a good night, countering Mr Trump’s nasty nativism with a touching tribute to an immigrant grandfather who spoke Spanish, and used that language to teach the young Marco to love America.

For the professional pundit crowd in the spin room and press tent where Lexington spent the evening, it was harder to reach a clear verdict about Ben Carson, a retired paediatric neurosurgeon and stern Christian conservative, who is in second place in many polls after closing fast on Mr Trump. Mr Carson’s style is low-key to the point of near-somnolence. He was anything but impressive when it came to explaining his plans for a flat tax (“It’s all about America,” he mumbled drowsily, before attacking progressive tax rates as “socialism”).

The problem for pundits is that opinion polls have proved conventional judgments wrong again and again this season, as Republican primary voters flocked to candidates whose merits are hard to identify. For several months, the key to the mystery seemed to lie in anger. Voters are angrier than ever before with Washington and the political class, it could be stated with confidence. According to this theory Republican voters in 2016 are a bit like the Tea Party in 2009 and 2010. They loathe Barack Obama and the Democrats with a passion and despise Republicans in Congress for failing to thwart him, despite controlling both the House of Representatives and the Senate. That rage is joined by seething suspicion of any promises made by politicians.

Off with their heads

There is some evidence for this theory. Polls show majorities of Republicans scorning political experience and saying they want an outsider to shake up Washington. Governors and senators and other grandees who thought they had worked out how to woo conservatives, by stressing their records of unyielding right-wing purity, found their years in office being held against them (while the same angry voters seemed willing to forgive Mr Trump any number of breaks with conservative orthodoxy, from his past donations to Democrats to his calls to whack hedge-fund bosses with higher taxes). So low-trust is the mood among Republican voters that several White House hopefuls, in an effort to pander to them, spent more time attacking each other than denouncing the Democrats. Standing at a podium in front of the gleaming airliner used by Ronald Reagan as Air Force One, Governor Bobby Jindal of Louisiana cast caution to the wind, ignored Reagan’s “11th commandment” about never speaking ill of fellow-Republicans and declared: “I am angrier at the Republicans in DC than I am at the president.” Given the current mood coursing through his party, the remark made sense.

But even this theory needs revising. For while Republican voters are exceedingly angry and mistrustful, their lynch-mob rage is selective. Mr Carson could hardly be less fiery (though he primly disapproves of many things), yet he is surging. And the same conservative activists who disbelieve the establishment on all fronts are startlingly willing to give outsider candidates like Mr Trump, Mr Carson or Ms Fiorina, the benefit of the doubt. So highly trusting are rank-and-file Republicans that—to the despair of pundits and fact-checkers—they shrug when Mr Trump refuses to provide any details about how he would handle foreign affairs, breezing that once he is president: “I will know more about the problems of this world”. Nor do they seem fussed to be told that Ms Fiorina’s time as a CEO was marked by massive job losses, after a bungled merger. A fourth anti-establishment candidate, Senator Ted Cruz of Texas, seems able to tap into this mood of strangely extravagant trust, by playing up his credentials as a serial rebel and critic of party leaders in the Senate.

Republican primary voters are not in a revolutionary mood, then, but a regicidal one. They think their rulers are corrupt, inept and mendacious, if not actually treasonous. But they are at the same time ready to swoon before new rulers promising to fix America in an instant. The key credential required to earn that trust is a lack of experience. Will those outsiders disappoint their followers in their turn, triggering a still deeper loss of public trust? Probably. This is going to be a bumpy year.