Just 33 percent of Germans would vote for Merkel's CDU if there were a general election this week, the Deutschlandtrend survey for public broadcaster ARD found – a fall of one percentage point since March.
It's a far cry from the 41.5 percent the centre-right party achieved at the last national elections in 2013.
Insurgent right-wing populist party Alternative for Germany (AfD) remained steady at around 14 percent support, despite a broadside of outrage this week over anti-Islam policies leaders announced on Sunday.
Pollsters Infratest Dimap found that 67 percent of people did not trust in the current government to fend off the risk of old-age poverty in the future.
Pensions and support for seniors look set to be the key battleground for the 2017 general election campaign, as economic experts warn of looming gaps in pension funds in the coming decades.
Meanwhile, the German public were approximately evenly divided on the refugee question, with 52 percent saying the government would not get the situation under control against 46 percent who still had faith in Berlin.
'Too much care for Erdogan'
A large majority of people said that Merkel was allowing concern for Turkish President Recep Tayyip Erdogan to influence her decision-making too much in a Politbarometer poll for broadcaster ZDF.
At 80 percent, an overwhelming number of respondents thought Merkel was wrong to not block a possible prosecution of TV satirist Jan Böhmermann for the antiquated crime of “insulting a foreign head of state”.
Böhmermann, who read a “smear poem” on air to mock Erdogan's thin-skinned complaints over a satirical song from a rival TV show, could now face a trial if prosecutors decide he has a case to answer under the 19th century statute.
Merkel has been criticized for allowing her fear of undermining a refugee swap deal with Turkey to influence her choice when it came to securing the fundamental right of freedom of speech and art at home in Germany.
Her junior coalition partners the Social Democratic Party (SPD) disagree so strongly that they have announced a bid to overturn the law immediately.