Voters in two eastern German states are about to go to the polls in elections that could see the far-right Alternative für Deutschland (AfD) party score its first wins at the regional level and a separate new populist force on the left establish a firm foothold.

The results in Saxony and Thuringia, due on Sunday evening, are expected to be disastrous for the three ruling parties in Chancellor Olaf Scholz’s centre-left-led coalition government in Berlin, one year before Germany holds its next general election.

Many eastern voters say they are increasingly disillusioned with mainstream politics more than three decades after national reunification, with the lingering impact of structural decline, depopulation and lagging economic performance compounding a sense that they are still second-class citizens.

“The AfD has built up a core base [in the east] that now votes for it out of conviction, not just owing to frustration with the other parties,” said Prof André Brodocz, a political scientist at the University of Erfurt in Thuringia.

The anti-migration, anti-Islam AfD spent the last week of its campaign hammering home the message that the government is “failing” its citizens, while harnessing shock and outrage over the deadly mass stabbing in the western city of Solingen allegedly by a Syrian rejected asylum seeker.

The party, whose Saxony and Thuringia chapters security authorities have classed as rightwing extremist, could come out on top in both regions, as well as in Brandenburg, the rural state surrounding Berlin which will vote on 22 September, polls show.

The 11-year-old AfD clinched its first mayoral and district government posts last year but has never joined a state government. The remaining, democratic parties have vowed to maintain a “firewall” of opposition to working with the AfD, keeping it out of power.

Its co-leader in Thuringia, Björn Höcke, has repeatedly used banned Nazi slogans at his rallies and calls for an “about-face” in Germany’s culture of Holocaust remembrance and atonement.

He aims to achieve a blocking minority of one-third of the votes in Thuringia, where the Nazis first won power in a German state government in 1930 before consolidating control in Berlin three years later.

At a rally in Erfurt days before the election, Höcke told a cheering crowd that he and the AfD were the only ones standing in the way of the “cartel parties” working to “replace the German people” with a “multicultural society” under a “totalitarian dictatorship”.

Scholz’s coalition of the centre-left Social Democrats, the ecologist Greens and the liberal Free Democrats was already on the backfoot and each of the parties has reason to dread Sunday’s election night results.

Riven by ideological differences and personal rivalries, the government has repeatedly stumbled in recent months in realising its main policy initiatives including kickstarting the moribund economy and getting more electric vehicles on German roads. The Greens co-leader, Omid Nouripour, recently described the coalition in Berlin as a “transitional government” in the period after Angela Merkel’s 16 years in power.

If the governing parties fail to clear the 5% hurdle to representation in either of the states on Sunday – which opinion surveys indicate is possible – coalition building could prove highly tricky.

The leftwing but socially conservative Sahra Wagenknecht Alliance (BSW), named after its firebrand leader, whose calls for higher taxes on the rich, a tougher line on migration and asylum, and an end to military support for Ukraine have struck a deep chord in the ex-communist east, could prove key in any coalition talks.

It is polling at about 11% in Saxony and 17% in Thuringia.

Her party’s rise was described as a “gamechanger” by Brodocz, underlining the rejection of the established political parties while offering disaffected easterners an alternative to the AfD, which many see as too radical.

Wagenknecht, already gearing up for the 2025 federal elections, has suggested she would drive up the price for joining any coalition, demanding “diplomacy” toward Russia while railing against a recent decision for the United States to begin deployment of long-range missiles in Germany from 2026.

The conservative opposition Christian Democratic Union party (CDU), which is leading in the national polls, could still eke out a victory in Saxony as it did five years ago, putting wind in the sails of its national leader, Friedrich Merz, who aims to challenge Scholz in the general election.

In Thuringia, it could come in second behind the AfD and then hammer out an ideologically awkward ruling alliance with smaller parties including Wagenknecht’s.

Merz has vowed the CDU will never work with the extremists but has moved his party steadily rightward, particularly in its migration rhetoric, during the post-Merkel years.