Merkel faces further threat from the far-right—this time it’s in Berlin

German Chancellor Angela Merkel's party is set for further losses in regional elections in the capital Berlin on Sunday, with the right-wing populist Alternative for Germany (AfD) party expected to make gains.

Support for Merkel and her conservative Christian Democrat Union (CDU) party has been hit by her open-door migrant policy, with a record number of people moving to Germany in 2015, according to official statistics.

This is expected to tell in Sunday's elections, which come after the CDU was knocked into third place by the AfD in regional elections in the region of Mecklenburg-Vorpommern earlier this month.

Voting in Berlin started at 7 a.m. London time Sunday and polling stations will close at 5 p.m. London time, according to Reuters. Public broadcasters will publish exit polls shortly afterwards.

"The negative implications of yet another strong AfD performance will further increase the pressure on Merkel," Carsten Nickel, deputy director of research at Teneo Intelligence, said in a report on Wednesday.

The AfD party was formed in 2013 and is Euroskeptic and anti-immigration. It is allied with the increasingly popular far-right Freedom Party of Austria.

Nickel forecast that a poor performance by the CDU on Sunday would prompt its sister party, the Christian Social Union (CSU), to again demand controls on Germany's annual refugee intake. Merkel has championed taking in victims of the chaos in Syria and Iraq and, consequently, German net immigration reached a record high of 1.139 million last year.

"The CSU will continue to criticize Merkel over migration," Nickel said.

"The goal is twofold: keep the AfD in check, and use the migration issue for the CSU's traditional strategy of extracting expensive CDU concessions on the economic, infrastructure, and security fronts."

Further ahead, the key test will be whether Merkel gets the CSU's backing for the federal elections in 2017.

"The next signpost to watch will be whether the CSU officially backs Merkel in time for the December CDU federal conference. But even if the Bavarians delay their decision until early 2017, the lack of alternatives means that time is on Merkel's side," Nickel said.

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