BERLIN — Five years ago, the nationalist Alternative for Germany sent the country’s traditional parties scrambling when it finished ahead of Chancellor Angela Merkel’s conservatives in the regional vote in the eastern state of Saxony-Anhalt, an ominous portent of the far right’s growing allure.
This Sunday, voters in Saxony-Anhalt will be back at the polls, and the result of this state election, coming just three months before a national one, will be scrutinized to see whether a nationally weakened AfD can hold on to voters in one of the regions where it has proved strongest.
While much about the Saxony-Anhalt contest is unique to the region and heavily focused on local issues about schools and economic restructuring, a strong showing by the AfD — which rode a wave of anti-immigration sentiment in 2016 — could cause headaches for Armin Laschet, the leader of Ms. Merkel’s Christian Democrats. Mr. Laschet, who is hoping to replace her in the chancellery, has struggled to gain traction in the former East German states.
“A strong showing by the Christian Democrats would remove a hurdle for Mr. Laschet and could strengthen his position heading into the national race,” said Manfred Güllner, who heads the Forsa Institute political polling agency.
At the same time, he conceded, “If the AfD were to perform as well as the Christian Democrats, it would have repercussions for the federal vote.”
Amid an election campaign largely carried out online because of pandemic restrictions, Mr. Laschet visited the state’s mining region last weekend. He stressed the need for time and investment to shift successfully away from coal and pledged to provide support similar to what his home state, North Rhine-Westphalia, got when it quit coal.
The effort may have paid off: A survey released on Thursday showed his party at 30 percent support in Saxony-Anhalt, a comfortable margin of seven percentage points ahead of the AfD, which is known by its German initials and currently holds 88 seats in the German Parliament.
If that margin holds, it could bolster Mr. Laschet’s standing as campaigning begins in earnest for the Sept. 26 election, despite a bruising contest for the chancellor candidacy against a rival from Bavaria.
In 2016, Germany was adjusting to the arrival of more than one million migrants the previous year, and Saxony-Anhalt was struggling against looming unemployment. While pollsters had predicted that the AfD, which made itself the anti-immigration party after forming in 2013 to protest the euro, would easily earn seats in the statehouse, no one expected it to come in second, winning more than 24 percent support from the region’s two million voters.
Since then, Alternative for Germany has swung even further to the right, capturing the attention of the country’s domestic intelligence service, which placed the AfD leadership under observation over concerns about its anti-Semitic, anti-Muslim expressions and links to extremists. The AfD’s branches in Brandenburg and Thuringia are also under scrutiny, while an attempt to observe the national party has been put on hold pending the outcome of a legal challenge.
The AfD in Saxony-Anhalt “has become very strong, despite the various messy and dubious scandals,” said Alexander Hensel, a political scientist at the Institute for Democracy Studies at the University of Göttingen, who has studied the party’s rise in the region. “Instead of breaking apart, they have consolidated, becoming an increasingly radical opposition force.”
The continued support for Alternative for Germany in places like Saxony-Anhalt has created a split among many mainstream conservatives over whether the Christian Democrats should be willing to enter a coalition with the far-right party if needed.
Mr. Laschet has made his opinion clear in recent days. “We don’t want any sort of cooperation with the AfD at any level,” he said in an interview with the public broadcaster Deutschlandfunk.
But with the jockeying for the future direction of the Christian Democratic Union underway after 16 years under Ms. Merkel’s largely centrist leadership, some members on the party’s right flank see her exit as a chance to shift harder to the right.
In December, the conservative governor of Saxony-Anhalt, Reiner Haseloff, a Christian Democrat who is running for another term, fired his interior minister for seeming to float the possibility of a minority government, supported by the AfD.
Mr. Haseloff has based his campaign on promising stability as the country begins to emerge from the pandemic, with a pledge to help improve the standard of living in rural areas, many of which lack enough teachers, medical professionals and police officers.
Saxony-Anhalt has the oldest population in all of Germany, a reflection of the number of young people who left the state in the painful years after the reunification of Germany’s former East and West in 1990.
While the state has benefited from an attempt under the latest government to create jobs in less populated areas, including by setting up several federal agencies in Saxony-Anhalt, the region’s standard of living still lags those in similar regions in the former West Germany, Mr. Haseloff said.
“There continue to be clear differences between east and west, and not only in the distribution of federal offices,” Mr. Haseloff said this week, ahead of an annual meeting focused on increasing regional equality.
The Alternative for Germany has campaigned this time around on a rejection of the federal government’s policies to stop the spread of the coronavirus. “Freedom Instead of Corona Insanity” reads one of its posters, showing a blue-eyed woman with a tear rolling down to the rim of her protective mask.
Among the other parties, the Social Democrats and the Left are both polling in the 10 to 12 percent rage, largely unchanged from where four years ago.
Both the Free Democrats and the Greens are predicted to see their popularity roughly double from where they stood in 2016, which could make it easier for Mr. Haseloff to build a government if he is returned to office. Analysts said regional gains for them were unlikely to have wider repercussions for the national race.
“Saxony-Anhalt is a very specific situation, they are coming from a unique history,” Mr. Hensel, the political scientist, said. “But regardless of whether the Greens earn 10 percent or the Free Democrats 8 percent of the vote, a quarter of voters support the AfD. That is worth paying attention to.”