Germans will cast two votes: one for a candidate in their constituency and one for a political party. The process is called a personalized proportional representation system. Simply put, Germans vote to decide how the 598 base seats in the Bundestag will be divided among members of Germany's various political parties.
"The Germans are all about proportion," said Jackson Janes, president of the American Institute for Contemporary German Studies at Johns Hopkins University. "The two votes boil down to what's their favorite guy who represents them in their districts and what's their favorite team that will represent them in the Bundestag."
The first vote, on the left side of the ballot, is a direct vote for a member of parliament in that constituency, similar to Americans voting for a congressional reprentative in their district. There are 299 constituencies in Germany, so direct votes make up roughly half of the seats in the Bundestag.
The second vote, on the right side of the ballot, is for a political party. Parties in Germany's 16 states put together lists of candidates; the results from the second votes determine which candidates make it off the lists to the remaining 299 seats in parliament. Parties need to receive at least 5 percent of the second votes in a state to qualify for a seat.