Angela Merkel may be poised to enter her fourth term as German Chancellor, but the chances of her serving the full four years are becoming increasingly slim, according to her far-right challengers the AfD.

The incumbent leader and her Christian Democratic Union (CDU) party are expected to enjoy an easy slide to victory when Germany heads to the polls on September 24, gaining an almost 50 percent lead on her closest competitors. However, dissatisfaction with public policy and European Union frustrations will undermine her efforts to stay the course, founding member of the AfD, Frank-Christian Hansel, told CNBC.

The latest INSA poll released Tuesday shows the CDU and its sister Christian Social Union (CSU) party gaining 37 percent, a notable lead on the second- and third-largest parties, the Social Democratic Party (SDP) and the anti-immigration Alternative for Germany (AfD), which are forecast 25 percent and 10 percent respectively. Still, the CDU will have to form a coalition to gain a parliamentary majority.

Christian Democratic Union + Christian Social Union – 37%
Social Democratic Party (SPD) – 25%
Free Democratic Party (FDP) – 9%
Green Party (Greens) – 7%
Die Linke (The Left) –9%
Alternative for Germany (AfD) – 10%

“The problems are getting so big with the migration crisis etc. that this next government will not be in power for the full four years,” Hansel said over the phone, insisting that Merkel’s efforts to appease all voters are unsustainable amid rising European pressures.

Merkel has attempted to broaden the appeal of the center-right CDU since taking to the helm of the party in 2005 but has struggled in recent years to strike an appropriate response to divisive issues such as the EU migrant crisis.

Since 2015, Germany has taken in more than a million migrants. The issue threatened to be the leader’s undoing at the start of the year, when she suffered a huge drop in support following a number of terror attacks in 2016. In her re-election campaign she has sought to address this, telling crowds at a rally on Monday “of course we can’t allow a year like 2015 to recur every year.” But her pledges were met by AfD supporters chanting “Merkel out” and “immigration needs clear rules.”

“The CDU will have to ask itself whether it is with the bourgeoisie or on the more liberal side. It can’t be both,” he argued.

Polling suggests that the AfD will win above the five percent minimum voter threshold needed to enter into parliament.

This will be the first time that a populist right-wing party, which counts a number of right-wing extremists among its members, has done so since the end of World War II. It marks a sudden rise in popularity for the party which launched in just 2013.

Though the Eurosceptic, anti-immigration party is unlikely to form part of a coalition government, it may hope to capitalize on this new position in parliament, seeking to align itself with other conservative members of parliament. However, according to Josef Janning, head of the Berlin office and senior policy fellow at the European Council on Foreign Relations, the AfD’s arrival will likely prompt the CDU to shift its stance in order to suppress the AfD’s influence.

“AfD presence will contribute to moves among CDU and CSU to better cover their conservative wing,” Janning said via email Tuesday. “The CDU, which has moved to the center with Merkel effectively occupying ground formerly held by conservative SPD, will likely move to the right.”

David Lea, senior analyst for Western Europe at Control Risks, agreed that given the resistance to the AfD from opposition parties, its influence in overall decision making will be limited, despite the symbolism of a far-right party entering into Germany’s post-war parliament.

“Entering as a minority party outside of any coalition, the AfD will not be that influential and will remain very much on the fringe,” Lea told CNBC over the phone Tuesday.

The notion that Merkel’s chancellorship could be coming to an end is not new, but unlike Hansel, analysts suggest that such a move will be Merkel’s own decision. In her previous term, Merkel herself suggested that she would not run again but then went back on the comment.

“I do think it’s possible that (Merkel) steps down, but that would be as much from her own volition as anyone else’s,” Lea noted.

He suggested that Merkel could step down mid-term to enable her successor to get their feet under the table ahead of the next election in four years’ time.

However, this is not something that she will announce before September’s election, according to Janning.

“For Merkel, any announcement of her not to serve for the full term would immediately weaken her standing as Chancellor,” Janning said. “So, she will not give any advance warning, should she be willing to abdicate at some point.”

Her likely successor is not yet apparent, though the task of finding one as adept at managing the power balance within Germany’s coalition politics will be a difficult one, possibly prompting internal struggles within the CDU/CSU, Lea suggested.

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