Across western democracies, political turmoil reigns as voters oust incumbents and elect new faces to lead them out of international and economic crises.
While the country has been beset by the same problems gnawing at other western nations — terrorism, influx of refugees, the recent global financial meltdown and the threat of war just about everywhere — Germany has emerged under Merkel's steady leadership with a booming economy and a desire by most voters to keep things that way.
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It helps that Germans are averse to radical change and find stability comforting.
"This isn't a time for experimentation," said Ralf Welt, managing director of Dicomm Advisors, a political consultancy firm based in Berlin. "This is a time in which people are basing their assessments on established trust. They don't want to start over with a new chancellor."
Her conservative Christian Democrats currently lead their closest competitor, the left-leaning Social Democrats, by 17 points in the national parliamentary elections, according to public broadcaster ARD.
"For me, Angela Merkel is the best chancellor that Germany has ever had," said Dieter W. Welle, 72, a retired engineer in Berlin. "She avoids political games and minimizes difficulties. Her achievements are incredible."
Merkel has been vulnerable for her "open door" policy that allowed 1 million refugees fleeing war and other migrants to enter the country since 2015. But a public backlash has been cushioned by satisfaction with economic conditions. Growth is strong, unemployment and inflation are low, real wages are rising and Germany enjoys a large budget and trade surplus.
Anger over absorbing so many migrants — which half of Germans say remains the most pressing problem, according to a September poll by German public broadcaster ZDF — has led to the rise of a far-right, anti-immigrant Alternative for Germany (AfD).
That party garnered more votes than Merkel's Christian Democrats in local elections in her home district of Mecklenburg-Western Pomerania last year. The AfD is trailing far behind in Sunday's election, yet it's likely to cross the 5% threshold needed to gain seats in the national parliament, or Bundestag, for the first time.
Merkel refused to remove her welcome mat for migrants, but mindful of the backlash she slowed the flood of refugees to a trickle by negotiating a deal with Turkey to accept new migrants trying to enter Europe.
"The events of 2015 and 2016 will not repeat themselves," Merkel told a town hall meeting on Sept. 11. "But you have to have an open heart for those who are much worse off."
A former chemist who grew up in East Germany, where her father was a Lutheran minister, the normally stoic chancellor has used her vehement defense of her refugee policy to showcase her steely resolve. The issue also provided an opportunity for her to show empathy with the plight of people escaping persecution and reveal a softer, more emotional side that appeals to voters on the left.
Events of the past year have allowed Merkel to demonstrate that she is not only a strong leader for Germany, but for all of Europe — and maybe even the entire free world.
When the British voted last summer to leave the European Union and President Trump sharply criticized NATO, Merkel was an ardent defender of a united Europe and a policy of common defense.
She also has been a leading critic of Russian aggression in Ukraine, played a crucial role in navigating the continent through years of financial crisis and a staunchly opposed Trump's decision to pull out of the Paris accord to combat global warming.
The chancellor's main competitor, the Social Democrats' Martin Schulz, has failed to inspire the public. His platform of reducing income inequality and reforming social welfare programs isn't resonating in a country enjoying good economic times now.
"The topic of social justice lost traction because the population more or less believes that they're doing pretty well economically and that we don't have a grave situation of social injustice in the country," said political consultant Welt.
Assuming she wins Sunday, Merkel's top challenges for her new term will include negotiating tough terms for Britain to pull out of the EU, avoiding another European financial crisis, and restoring faith in Germans' beloved but scandal-ridden auto industry.
In 2015, American regulators discovered Volkswagen has been cheating on emission tests for diesel cars that were supposed to be the new wave of German technology. Since then, other German auto giants that include Daimler and BMW did so, too.
"A lot of trust has been destroyed," Merkel said recently at the 2017 International Motor Show in Frankfurt. "The industry must do everything to win back credibility and trust — in its own interest and that of employees and German industry."
Gracefully addressing these challenges is crucial for Merkel, who doesn't want to be remembered solely for her controversial refugee policy, said Gero Neugebauer, a political scientist at Berlin's Free University. "When she looks back in 10 years at her last term, she wants to be sure that she had a worthwhile ending comparable to her predecessors," he said.