The German leader made the unusual step to directly phone voters in a desperate bid to persuade them to back her party CDU’s candidate in Hesse, home to Germany’s financial capital, Frankfurt.
Angela Merkel is desperate to claw back power in the state, one of the CDU’s traditional strongholds.
But with support for the far-right Alternative for Germany (AfD) and the Greens rising, there are growing predictions the CDU will lose power.
The loss would further calls for Mrs Merkel to step down from her 13-year premiership and ultimately prompt a leadership challenge.
Images of Mrs Merkel phoning residents posted on Twitter exposes the chancellor’s fragility as she clings on to power after 18 years at the helm of the Christian Democratic Union (CDU).
Posting the photo, which shows Mrs Merkel on the phone, Nico Lange wrote: “Well, good morning, this is Angela Merkel. “Chancellor, Minister-President Bouffier and Annegret Kramp-Karrenbauer are motivating election campaigners of the CDU in Hesse with direct phone calls.”
Angela Merkel’s popularity has taken a battering after her open door policy saw more than one million African and Middle Eastern refugees arrive in Germany in 2015.
The German Chancellor’s party is set to receive only 26 percent of the votes at the upcoming state election in Hesse, according to a survey by pollster Forschungsgruppe Wahlen for broadcaster ZDF.
This would represent a 12 percent drop for Mrs Merkel’s party compared to the Chancellor’s results in the region’s last election in 2013, when the party won 38.3 percent of the seats.
After huge losses in last year’s elections, Mrs Merkel this summer faced the biggest threat to her power when Horst Seehofer, who is her interior minister and leader of the Christian Social Union (CSU) leader, threatened to close Germany’s borders to migrants.
The German leader was forced into a corner when Mr Seehofer threatened to defy her wishes and order police to turn back asylum seekers unless she secured a broader EU deal on distributing migrants more evenly.
The move could have forced Mrs Merkel to sack him, triggering the collapse of her three-month-old government as well as the EU’s Schengen zone of free travel.