Within minutes of Wednesday night’s exit poll D66 leader Rob Jetten stepped up on stage in Leiden, pumped full of confidence, and declared it was time to “turn the page on Wilders and work towards a great future for the Netherlands”.

In his enthusiasm Jetten seemed to have forgotten the first rule of Dutch politics: write Geert Wilders off at your peril. And sure enough, by daybreak it became clear that the book was far from closed on the far-right leader.

It was a stunning result for D66 and one there was little hint of as the election campaign got under way in mid-September, when Jetten’s party was back in fifth place, around 18 seats behind the PVV.

The party climbed steadily at first and then accelerated, with a campaign targeted squarely at the centre ground, combining a “tough but fair” stance on asylum and migration and plans to develop cheap, renewable energy with investment in education and technology, recognition for a Palestinian state and a European army.

D66 took votes from the shipwrecked NSC, from GroenLinks-PvdA, from VVD voters who were alienated by Dilan Yesilgöz’s move to the hard right, from potential Christian Democrats who were unsure of Henri Bontenbal’s views on Christian schools from non-voters and even from the PVV.

Television debate

Jetten benefited from some strokes of fortune: he was a last-minute replacement for Wilders in the opening television debate after Wilders pulled out, ostensibly for security reasons.

His party offices were attacked when an anti-immigration protest in The Hague turned into a full-scale riot, allowing him to denounce the influence of far-right ideology in parliament.

Even his appearances on the popular TV quiz De Slimste Mens (“The Smartest Person”), which was recorded months earlier but broadcast during the campaign, was credited with boosting his screen time.

But Jetten took the breaks well. His television performances were polished and upbeat, in contrast to his early days when he was mocked as “robot Jetten” for his heavily scripted answers and wooden delivery.

And he judiciously refrained from dwelling on the attack on his offices in The Hague after the first few days, preferring to focus on the positive aspects of the D66 campaign.

More than anything, Jetten seemed to capture the mood among voters who were disillusioned after two years of stagnation and in-fighting in the right-wing coalition formed by PVV, NSC, VVD and the farmers’ party BBB.

“Positive forces”

While Wilders painted an apocalyptic picture of a country ruined by mass migration and out-of-touch leaders, Jetten had a more hopeful vision, encapsulated in D66’s Obama-influenced slogan Het kan wél.

“Politicians in the Netherlands should be more optimistic and ask how we can make our country better, instead of talking each other into the ground the whole time,” he told Dutch News.

He depicted the Netherlands as a nation with vast potential that had suffered from leaders who lacked the vision to unlock it. The country was not angry, as Wilders kept hollering, just disappointed.

The “positive forces” Jetten referred to during the campaign were epitomised by his headline policy of building 10 new cities.

Where other parties talked of adding a street here and there to fix the housing crisis, D66 had ambitious plans to build not just houses, but bright modern neighbourhoods with schools, public transport links and green spaces, using innovative technological solutions.

Jetten explicitly referred to the Delta works, invoking memories of a time when the Netherlands was celebrated for its world-beating engineering skills.

Far-right remains strong

D66 is not averse to a spot of nationalism – witness the energetic flag-waving at the party’s election night celebrations in Leiden – but it prefers the progressive nationalism of the 20th century to the migrant-bashing of the 21st.

But the flip side is that if he becomes prime minister, Jetten will not be able to heal the Netherlands’ divisions overnight with a dose of political positive thinking.

The far-right vote has splintered but still accounts for nearly one-third of the seats in parliament. Some of the PVV’s share went to JA21, a party that has similar views on Islam and asylum but has not been ruled out as a coalition partner.

The even more radical, pro-Russian Forum for Democracy increased their share from three seats to seven. Wilders and the other populist right parties will continue to be a thorn in Jetten’s side and keep pushing the issue of immigration to the forefront of the public debate.

D66 is on course to beat the PVV by the narrowest of margins: the parties are level on seats, although Jetten could gain a psychologically significant one-seat advantage once the overseas votes are counted.

Coalition headache

Even then, 27 seats – less than a fifth of the total – is the smallest number ever for an election winner. Jetten will have to find at least three other parties for a coalition and none of the options are easy.

Jetten’s own preference is for a stable coalition of the centre, which would mean a combination with the right-wing liberal VVD, GroenLinks-PvdA and the Christian Democrats.

But that scenario has been complicated by the VVD’s unexpectedly strong performance and the fact that D66 took more votes from the left than from the progressive wing of the VVD.

The latter party’s leader, Dilan Yesilgöz, firmly ruled out joining a government with GL-PvdA, and being the second largest party in the quartet will give her considerable leverage.

Yesilgöz wants to see a “centre-right cabinet with a strong VVD”, which realistically would mean swapping out GL-PvdA for JA21, a party that has little in common with D66.

But on current numbers that quartet would fall just short of a minority in parliament and have serious challenges getting laws passed by the Senate, where the parties have less than one-third of the 75 seats.

The need to bring a fifth party on board could give Jetten an opportunity to balance JA21 with the ChristenUnie, which has three seats and worked well with D66 in Mark Rutte’s last two cabinets, despite their ideological diifferences.

The only snag would be that Rutte’s last cabinet collapsed two years ago when his justice minister demanded tough restrictions on bringing in asylum seekers’ families, which the ChristenUnie, as a party of strong family values, firmly rejected.

The justice minister in question was, of course, Dilan Yesilgöz.