RASTATT, Germany (Reuters) - Gerd Mueller has voted for Chancellor Angela Merkel’s conservative Christian Democrats (CDU) for over 40 years. Now he’s having second thoughts.

Joerg Meuthen, co-chairman of the right-wing Alternative for Germany (AFD), answers questions for Reuters TV prior to an election campaign for the upcoming state elections in Baden-Wuerttemberg in Rastatt, southern Germany, February 22, 2016. REUTERS/Kai Pfaffenbach

“I am very irritated,” the 64-year-old said between business appointments in Rastatt, a well-off town of 50,000 near the border with France in Baden-Wuerttemberg, one of three German states holding elections on March 13.

“I don’t feel Frau Merkel is bringing us along with her,” he added, pointing to the German leader’s welcoming stance towards refugees.

Mueller’s frustration is shared by a rising number of voters. Elections next month in this prosperous southern state, its wine-producing neighbor Rhineland-Palatinate and Saxony Anhalt in the east will serve as a litmus test of Merkel’s migrant policies ahead of the next federal vote in 2017.

Facing the biggest test of her decade in office, Merkel is scrambling to secure a Europe-wide plan to address the refugee crisis but the rank and file of her party are losing faith in her ability to make it work. Many want Germany to close its borders instead.

A poor showing by the CDU in the state elections would increase pressure on the chancellor to reverse course, 1-1/2 years before the federal election, when she is likely to seek a fourth term.

In campaign appearances in recent weeks she has warned about the consequences for Europe of border closures. But her conservatives are watching nervously as they lose ground to the anti-immigrant Alternative for Germany (AfD), whose hardline stance on refugees could bring it big gains in all three states.

“If the AfD does really well in all three elections, it will be blamed on Merkel and her refugee policies,” said Frank Decker, political scientist at Bonn University.

“The stronger the AfD, the higher the pressure on the CDU.”

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In Baden-Wuerttemberg, a CDU stronghold for over 50 years before turning to a Green-led coalition in 2011 after Japan’s Fukushima nuclear disaster, polls put the AfD on 10 percent or more.

“The political establishment in this country is in such a dire state that voters have to look for an alternative,” Joerg Meuthen, 54, the AfD’s leader in Baden-Wuerttemberg, told a party rally in Rastatt on Monday, to loud applause.

An economics professor, Meuthen has sold himself as a moderate but the party is viewed by many as having far-right leanings. At the rally, banners read “Courage for Germany”.

At Meuthen’s side stood Manuel Speck, 24, a local plumber, who said he used to lean towards the Greens but was now standing as the AfD’s candidate in Rastatt as he believes Germany is on the wrong track.

“I don’t want to be asked in 70 years, ‘did you not know anything about this?’ and then have to say, ‘yes, we knew but we didn’t do anything about it’,” he said to loud applause from the 200 mostly older voters in attendance.

HIGH STAKES

The three states voting on March 13 have a combined population of some 17 million, a fifth of Germany’s 81 million.

In wealthy Baden-Wuerttemberg, home to luxury carmakers Porsche and Daimler, AfD gains could prevent regional CDU leader Guido Wolf, 54, from winning back power from the Greens, who are led by state premier Winfried Kretschmann, 67, a former teacher.In Saxony-Anhalt, a poll published this week showed the AfD overtaking the Social Democrats (SPD), Merkel’s coalition partner in Berlin, for the first time, a humiliation for a party that is girding for big losses on March 13.

To shore up his support in the eastern state, CDU premier Reiner Haseloff has publicly criticized Merkel’s plans for a European solution to the migrant crisis.

In the third state, Rhineland-Palatinate, Julia Kloeckner, a charismatic 43-year-old former German “wine queen” who has positioned herself as a candidate to succeed Merkel one day, has seen her lead shrink in recent weeks.

Kloeckner and Wolf, fearing a loss of support because of the refugee issue, teamed up to issue a joint statement on Sunday which said: “Without grounds for asylum or protection status, no one else should be allowed to come into our country.”

“There is only one winner for sure: that is the AfD party,” said Josef Joffe, publisher-editor of German weekly Die Zeit. “And that will heighten the pressure on Merkel to stem the refugee flow she herself has invited into the country.”