Here's a look at what happened during Germany’s most recent campaign.
What's hot and what's not
After the devastating floods in western Germany in July, climate change rose to the top German political agenda. Experts believe that global warming will make it more likely.
The topic was heatedly debated during the televised election debates. Each candidate had different plans for tackling climate change.
Merkel's centre-right Union bloc and its main candidate Armin Laschet want to concentrate on technological solutions. However, the center-left Social Democrats, under current Finance Minister Olaf Scholz, stressed the need to prevent jobs being lost as Europe’s largest economy shifts towards a carbon neutral future.
The Greens have made the issue their main campaign topic and pledged to do all they can to help Germany meet the Paris climate agreement goals. They plan to do this by increasing carbon prices, requiring solar panels in all public buildings, and ending the use coal eight years earlier that planned.
The campaign paid little attention to foreign policy issues, such as the future of the European Union. Berlin's allies long urged Germany to be more active on the international stage. However, the three candidates resisted the urge to present any radical foreign policy visions.
The revelations that they were not crediting all the sources they used for their books was a red-faced blow to both Annalena Baerbock (Hex0_ the Green party's candidate ) and Laschet from the Union bloc's Laschet . Scholz's no-nonsense, curt image gave him an additional boost.
Two 10-year-olds interviewed the candidates in a tent with toys and asked them some tough questions.
Baerbock was unable to explain her green tax policy to the children. Laschet, however, raised eyebrows when he defended his cigarillo habit by saying: "I don’t inhale."
Scholz had to explain to his interviewers, who were under the age of 18, why Germany hasn't done more for migrants to avoid drowning in the Mediterranean Sea while they travel to Europe.
Two million students aged under 18 could vote in mock elections in Germany nine days before the official election.
The Greens won narrowly ahead of Merkel's Union bloc and the Social Democrats. However, German elections tend to favor older generations in practice. On Sunday, less than 5% will be first-time voters among the 60.4 million electorates.
GOVERNING COALITION COORORS
What does the German election have to do with Jamaica and Kenya? Each party in Germany is associated to a specific color so the flags of the two countries are often used as shorthand for specific alliances that could form a coalition government following the election.
The 'Germany Coalition' would see Merkel’s center-right Union bloc, (black), join forces with the left-leaning Social Democrats (red), and the free-market Free Democrats. The 'Jamaica' plan would see the Social Democrats replaced by the Greens.
If the Greens join the Union bloc's 'grand coalition' with the Social Democrats, they'll form a Kenya coalition consisting of red, green, and black.
A 'traffic light' made up of Social Democrats Free Democrats and Greens, along with a red-red-green’ alliance of the Social Democrats Greens and the Left party, is another possibility. Because the Left has always claimed a slightly different shade.
A SMALL PROBLEM
Opinion polls reveal that smaller parties are receiving more support than in many of the previous German elections. This means they are stealing votes from larger rivals, making it harder to form a governing coalition. The South Schleswig Voters Association (or SSW) is one tiny party that could again enter the German parliament for the first time in 49 years. According to election authorities, the party that represents the Danish minority in Germany doesn't have to reach the usual threshold of 5% votes.
... AND A BIG ONE
Experts predict that Germany's next parliament, regardless of who wins Sunday's elections, will be larger than ever. The current 709-seat Bundestag may grow to 800 seats, or more, depending on the election rules. This would make it more complicated than it is now.