But with the departure deadline delayed until at least Halloween, the election is going ahead. That is bad news for the Conservative and Labour parties, which suffered losses in local elections this month that the Brexit Party did not contest.
But it is particularly awful for the Conservatives, many of whose usual supporters are livid that May has failed to deliver on Brexit; voters could desert the party in droves. In one recent poll on the European elections, the Conservatives were buried in third place, with 13 per cent, well behind the 30 per cent for the Brexit Party and 21 per cent for Labour.
Into that crucible has stepped Farage, perhaps the most divisive figure on the British political landscape, but also among the most effective.
He has taken to the stump and to social media with a simple message: that Britain should leave the European Union even without any agreement. In the process, he excoriates what he calls a Brexit betrayal by mendacious elites.
Most MPs and analysts think a no-deal Brexit would be economically disastrous.
Before the referendum, Farage breezily assured voters that securing a favourable trade deal with the European Union would be easy because German automakers would demand the right to sell their cars in Britain. Nowadays, he prefers to focus on issues of identity and sovereignty.
An admirer of US President Donald Trump, Farage was certainly popular among the mainly greying supporters who gathered one recent day on the pier at Clacton-on-Sea, once a thriving holiday spot in Essex, east of London, and now an unfashionable outpost at the end of a slow rail line.
What, he asked them rhetorically, would Brexit do for towns like this? "It would make us proud of who we are as a nation once again," he roared, "and you can't put a price on that."
Performances such as this have propelled Farage back to prominence, which has meant greater scrutiny and some awkward headlines, too.
Questions about the Brexit Party's funding were raised after Farage refused to identify its biggest donor, though Jeremy Hosking, a financier, later said he had made a large donation. And there was criticism of a speech Farage gave in the US in which he claimed that entire streets in one British town were divided on racial lines.
Newspapers have also reported claims that he walked away from a car crash without checking on the welfare of others involved, and that his beer-drinking pose is a gimmick, intended to make him appear down to earth, saying that he really prefers wine.
On Monday, Farage seemed to lose his cool during a BBC interview when challenged about past comments on immigration, climate change, gun control and President Vladimir Putin of Russia.
Nonetheless, experts acknowledge that Farage's raucous brand of politics has proved effective.
"One of the consequences of Brexit and the way that it has been handled is a rebooting of populism," said Matthew Goodwin, professor of politics at the University of Kent.
"Leavers are incredibly disillusioned and frustrated with the positioning not just of the Government but of Parliament."
While the Brexit Party's threat to the Conservatives is manifest and could accelerate May's promised departure from power, Farage also presents problems for the opposition Labour Party.
Labour is hampered by relying on the support of an awkward coalition: pro-Brexit voters in working-class areas in the middle and the north of the country; and younger, more liberal voters in London and other big cities who are ardent supporters of remaining in the European Union. Members have pressed the party to make a second Brexit referendum part of its election manifesto.
That split provides Farage with an opportunity.
"They feel they don't need to target Conservatives because they have Conservatives anyway," Goodwin said. "They feel they need to win over Labour voters in pro-Brexit areas."
As critics point out, Farage is hardly the political outsider and avatar of the common man that he presents himself as. He was educated at an expensive school and worked as a commodities trader before spending two decades as a member of the European Parliament and failing seven times to win election to the British Parliament.
But in Clacton-on-Sea, he talked of Brexit being "openly and willfully betrayed" by politicians and argued that "this political class, that these two parties, that Parliament now need to be swept aside and replaced by better people." At times, the rally had a pantomime feel as Farage named MPs, waiting for the crowd to boo or, in one case, yell "traitor!"
To fans like Eileen Kelly, 74, Farage is the man who "tells it like it is".
She said she voted for Brexit in 2016 largely because she was unhappy about immigration, and she describes the current impasse in Parliament as a "desperate, awful, situation".
As for Farage, she says: "He should be prime minister — definitely".
Within days of its introduction, the Brexit Party said that it had signed up more than 70,000 supporters at 25 pounds a person, and that it had begun advertising online.
In truth, Farage had been preparing for this moment for months and had put together a machine far slicker than that of a new pro-European party, Change UK, which emerged from a group of MPs who left the Labour and Conservative parties this year.
The biggest problem for the Remain forces — and an advantage for the Brexit Party — is that Change UK has several strong rivals for the pro-European vote. Those include the centrist Liberal Democrats; the Greens; the Scottish National Party; and the Welsh nationalists, Plaid Cymru — not to speak of the Labour Party, despite its ambivalence over a second referendum.
Although the system for European Parliament elections is more proportional than that for most votes in Britain, it still punishes smaller groups.
"If you knew these elections are coming up, why on earth don't you decide to organise a pan-party Remain alliance?" Goodwin said. "It beggars belief."
Farage has some competition from the UK Independence Party, which he once led.
It always contained some eccentric characters with the potential to cause embarrassment. Now it has taken a turn to the far right under its new leader, Gerard Batten, who appointed the notoriously anti-Islam activist Tommy Robinson as an adviser. Robinson is running in the European elections, but as an independent.
The split among Brexit supporters could cost Farage some votes. In Clacton-on-Sea, Chris Manning, 66, who voted for Brexit in 2016, said he was a supporter of Farage but had not followed the ins and out of whether or not Farage was still part of UKIP.
But Goodwin said it would be unwise to underestimate Farage. "The story of the last five years," he said, "is of nationalists and populists outperforming the others and mobilising much more successfully than those trying to retain the status quo."
Written by: Stephen Castle
© 2019 THE NEW YORK TIMES