Voters go to the polls across the EU from Thursday for elections to the European Parliament that reflect a continent largely politically in step, debating the same issues in sync.

It’s not so much the long-hoped-for coming-together of a common sense of Europeanness, but a reflection in many of the member states of a clash of profoundly different ideas about where Europe should be going.

In most states the verdict of voters will be on their own government, but the subtext is shared: the rise of populism or its containment.

The polling in 28 states with 350 million citizens of voting age will fill 751 seats in the parliament, dropping to 705 if the UK leaves the EU. Voting takes place in the UK and Netherlands on Thursday, and in Ireland and the Czech Republic the following day, with the rest to follow over the weekend.

This election is epitomised by two men: Matteo Salvini and Emmanuel Macron. The big election polemics are broadsides between them. And the contests across the EU, from Hungary to Finland, even in the curious sham poll in the UK, are to a great extent proxy battles between the ideas they broadly articulate.

The Italian deputy prime minister’s picture even appears on the election literature of Macron’s nemesis, Marine Le Pen. Her Rassemblement National, formerly Front National, is polling neck and neck with his La Republique en Marche on about 23 per cent, with traditional Gaullists and socialists eclipsed.

The conflicting Salvini/Macron visions of the future of Europe are profoundly at odds: Salvini’s curtailed ambition, returning powers to the member states and building fortress walls against outsiders, against Macron’s open, trading Europe that sees its strength in facing collective challenges together, in solidarity, and holding to the increasingly threatened rule of law.

In one national election after another, European voters have been deserting the mainstream centre-right and centre-left political parties that have ruled the roost since the aftermath of the second World War. Macron’s warning to all European voters in an opinion article appealing to “the citizens of Europe” was of “European civil war”. Can this seemingly irresistible tide be halted?

“We’re the ones who don’t want anything to do with Merkel, Macron and those who ruined Europe,” Salvini blasted back.

He has been campaigning for months – more than 200 rallies so far, spending only 17 days at work in his ministry, according to one paper. And it has been paying off: his far-right League party has in the past year gone from 17 per cent in Italy’s general election to 30-35 per cent in the polls.

French president Emmanuel Macron. Photograph: Marlene Awaad/Bloomberg

Far-right clones from across the Continent cling to his coat tails. Eleven populist party leaders from all over Europe turned up in Milan last weekend to bask in his success and pledge to make common cause. They came from France to Austria, the Netherlands, Denmark, Estonia, Finland, Germany and Slovakia. And there are like-minded governments in Hungary and Poland cheering him on.

Populist fortunes

A study by Politico shows gains for Eurosceptic parties in 16 members states, with Italy, Slovakia and Spain increasing their expected numbers by 20, five and five respectively.

But it’s not all going their way. The Austrian Freedom Party leader’s spectacular own goal that came to light last week – he was recorded promising government contracts in return for political patronage – will certainly curtail its vote, while Poland’s Law and Justice has seen its vote hit, polls show, by its association with the country’s Catholic Church enmeshed in a huge paedophilia scandal.

Even in Italy Salvini faces difficulties as his coalition partner, the populist Five Star Movement, distances itself from League and makes overtures to the centre-left Democratic Party.

An advertising board for the EU elections in Brussels. Photograph: Yves Herman/Reuters

There are signs that the tide may be starting to turn. Italian journalist Beppe Severgnini – perhaps in an exercise of wishful thinking – warns that the volatile Italian politics that has made Salvini may turn on him. “The mood is changing. It’s like marshmallows ... You can’t get enough of them, until you’re suddenly sick of them. And Matteo’s marshmallow moment may be coming sooner than most expect,” he wrote.

But if in Italy the far right is still in the ascendant, its brothers in arms in Germany, Alternative für Deutschland, may be faltering. Having entered the German parliament for the first time last year to become the largest opposition force, its share of the poll has edged downwards since the turn of the year, while the Greens and the Left party are making gains at the expense of the mainstream Christian Democrats and Socialists.

The AfD, fourth in the polls, is making the case to entirely abandon the European Parliament and for a fundamental reform of the EU that includes a return to a national currency. The party wants Germany to leave the EU if its reform agenda is rejected.

Chancellor Angela Merkel is keeping her head down, leaving campaigning to her successor as head of the governing CDU, Annegret Kramp-Karrenbauer.

Faragism sweeps UK

In the UK, the populist tide is most certainly in the ascendant with Nigel Farrage’s Brexit Party sweeping all before it, bringing a Tory humiliation into prospect. But a revived Labour vote may also help the European Parliament’s Socialist (S&D) group, boosted by a strong Spanish socialist revival, claim the spitzenkandidat crown for Dutch commissioner Frans Timmermans.

Brexit Party leader Nigel Farage, who looks set to sweep up the Tory vote. Photograph: Olga Akmen/AFP/Getty Images

MEPs hoped the spitzenkandidat system, under which the political groups use the elections to nominate their candidates for the presidency of the European Commission for approval by EU leaders, would give the elections a greater salience and relevance in citizens’ minds and an all-European character. It might even help boost turnout, which has fallen in every contest since direct elections to the parliament started in 1979 – from 62 per cent then to 42.6 in 2014.

Voters have yet, however, to show any sign of interest in the spitzenkandidat process, and the European People’s Party (EPP) candidate, Bavarian Manfred Weber, although favourite to come out on top, has achieved virtually no name recognition across the union.

The rise of populism and the expected strengthening of the Green and Liberal (Alde) groups in the parliament will ensure that the EPP and S&D will lose their ability to form a controlling majority in the parliament on their own.

Alliances of three or four parties will now be necessary either to nominate a spitzenkandidat or run the parliament’s business, and on the latest parliament polling projections the two major parties will together achieve only some 330 seats – well short of the 376 required for a majority. That means 104 votes from the Liberals and/or 55 from the Greens would be needed by Weber to secure the parliament’s nomination.

Alternatively, as he suggested in the recent Eurovision debate, Timmermans may yet be able to achieve a majority with a left-of-centre alliance – from “Macron to Tsipras”, as he put it – of Socialists, Greens, Liberals projected to win 364 votes. Just short of the majority.

The projections put the populist and nationalist Eurosceptic groups on a combined total of 143, but their ranks could be swelled by temporary support for unaffiliated neo-fascists as well as the defection from the EPP of a strengthened block of probably 13 Hungarian MEPs from that county’s governing Fidesz party.

Part of this febrile mix, for a few months at least, will be MEPs from the Brexit Party, expected to add 12 seats to the 24 won by Ukip in 2014.

Even without anything close to a majority, the populists will be able to make sustaining a legislative majority extremely difficult, not least because of their entitlement to multiple crucial committee chairs.

EUROPEAN PARLIAMENT ELECTIONS: THE PARTIES

– European People’s Party (EPP). Main centre-right group, to which Fine Gael is affiliated. Dominated by German Christian Democrats and French Gaullist parties, but also contains Hungary’s Fidesz (currently suspended from the group) and Silvio Berlusconi’s Forza Italia.

– Progressive Alliance of Socialists and Democrats (S&D). Socialist parties and Italy’s Democratic Party. The (Irish) Labour Party is affiliated to this group.

– Conservatives and Reformists (ECR). Conservative, Eurosceptic group including British Tories, Polish Law and Justice and the far-right Brothers of Italy

– Alliance of Liberals and Democrats (Alde). Contesting elections in alliance with Macron’s En Marche; includes Fianna Fáil

– Confederal Group of United Left and Nordic Green (Gue/NGL). Hard-left group; includes Sinn Féin.

– Greens and European Free Alliance (G/EFA). Green parties, including Ireland’s.

– Europe of Freedom and Direct Democracy Group (EFDD). Eurosceptic group involving Brexit Party and Italy’s Five Star Movement

– Europe of Nations and Freedom (ENF). Hard-right Eurosceptics, including France’s Rassemblement National, Italy’s League, Austria’s Freedom Party and relics of Ukip.