It is called a general election, but Friday night’s multiparty debate was a reminder that it is also a messy array of specific elections. Over on one side of the stage, Penny Mordaunt and Angela Rayner traded blows in the prize fight between incumbent power and the only challenger that can supply a replacement government. First on defence, then on tax and the cost of living, the Tory leader of the house piled into the deputy Labour leader in full Westminster pugilism mode. Rayner defended herself gamely and landed a few jabs in return. More than once Mishal Husain, a coolly professional umpire throughout, had to separate the combatants. “That was terribly dignified, wasn’t it?” Carla Denyer, co-leader of the Greens, commented sarcastically from her vantage point in a very different election. Her arena is the handful of seats where Greens are, as she said, “on the cusp of breaking through” – including Bristol Central, where she is trying to oust a sitting Labour MP. To coax liberal and left-leaning voters to a small challenger party, Denyer needs two factors to come together. First, there must be confidence that Rishi Sunak is finished; that there is no danger of his party still being in power after 4 July. Second, there should be a dispiriting feeling that Keir Starmer’s Labour party doesn’t represent a radical alternative. Judging by audience reaction, both conditions are met. Over on the opposite end of the spectrum, Nigel Farage was working the same political geometry, but with the symmetry flipped. Reform UK is also fishing for support in the pool of voters who see Labour and Tories as two sides of the same debased coin, but his audience is disillusioned ex-Conservatives. Farage was dismissive of Labour, but his rhetorical firepower was directed almost exclusively at Mordaunt. His specific election is the one that will decide what the opposition will look like once Keir Starmer is prime minister. Mordaunt didn’t take the bait, partly because she was fighting yet another mini-election – the contest to be the next leader of her party on the assumption that Sunak will be gone soon enough. In that race, the electorate of Tory MPs and activists might be generously disposed to Reform. There might even be talk of a merger. So her future candidacy prevents overt repugnance at Farage. Except to reach that stage, Mordaunt has to hold her Portsmouth North seat. There another micro-election popped into view. While ostensibly representing her party, the Tory representative on the panel was sure to lever in plenty of mentions for her local constituency. The objective of saving her own electoral skin explains also why she made no effort to defend Sunak when he came under attack for sloping off early from this week’s D-day commemorations in Normandy. Nor did she try at any other point to recommend her leader as a strong candidate to continue being prime minister. For Mordaunt, the stage was an audition to be part of the future of the Conservatives, not a serious attempt to redeem its recent past. For Stephen Flynn, of the Scottish National party, and Rhun ap Iorwerth, of Plaid Cymru, the election is by definition fought on separate parameters. Their party names won’t even be on the ballot for a majority of viewers watching the debate. They, too, have an interest in presenting the Tory-Labour contest as a foregone conclusion and an iteration of the status quo. On that score, Flynn, leader of the SNP’s Westminster cohort, probably had the best night of the seven debaters. He expressed the fictions that underpin Conservative and Labour budget commitments – the undeclared assumptions of billions of pounds of spending cuts at the bottom of the fiscal envelope – with cogency that has so far been lacking from the campaign. Flynn will also have gladdened pro-Europeans across the UK by making the banal but perversely taboo (in England) observation that Brexit has been an “unmitigated disaster for the economy”. He was the most succinct and focused foil to Farage, first on rejecting the NHS as a socialised healthcare model, and then when the argument turned to immigration. The Reform leader was never knocked out of his comfort zone. He knows his lines – blaming migrants for strain on public services and rising crime – and he knows his target audience. He’ll also relish the appearance of isolation, when four panellists – Flynn, ap Iorwerth, Denyer and Daisy Cooper for the Liberal Democrats – all weighed in with degrees of pro-migrant, liberal dissent. The intervention on that front, pointing out that a migrant you meet in the NHS is most likely to be the clinician treating you, was probably Cooper’s most memorable moment. In the overall scheme of things, one televised election debate won’t shift the dial on the way the issue is debated more generally. But it was refreshing to hear some progressive arguments aired more passionately and sustainedly than is usually the case. And it was instructive that the audience, chosen to be representative of the broad range of national opinion, seemed open to persuasion. Faragism might be a significant force in British politics in terms of the effect it has had on the Tories and its reach in the media but, in raw and pungent form, it is a minority taste. There isn’t much evidence that these debates make a difference to voting intentions, although they have a significant function in simply reminding people that smaller parties exist. And mostly they rose to the occasion. Meanwhile, Labour and Tories, the two heavyweight fighters, slug it out in the only way they know how; the way generations of Westminster culture and parliamentary arithmetic have trained them to do, even if the audience craves a different spectacle. Rafael Behr is a Guardian columnist