A look at the voting system used in Germany's parliamentary election

BERLIN – Each of Germany's nearly 62 million eligible voters can cast two ballots in Sunday's parliamentary election — one for a directly elected representative and the other for a party.

Half of the seats in the lower house of parliament, or Bundestag, go to the directly elected lawmakers, one for each of the 299 constituencies. They are elected by a simple majority.

The other 299 seats are allocated to candidates elected by party lists. The party vote is critical because it determines the percentage of seats each party wins in the lower house, which in turn selects the chancellor.

To share in the division of seats, a party must win 5 percent of the second type of vote or have at least three directly elected lawmakers.

However, if any one party wins more seats through the direct vote than it would be allotted under the distribution based on the party vote, the system allows that party to keep the extra seats.

These extra seats, called "overhang" mandates, can bump up the number of lawmakers in parliament. The last election, in 2009, produced a parliament with 622 lawmakers rather than the minimum 598 — with Chancellor Angela Merkel's conservative bloc picking up 24 extra seats that padded her center-right coalition's majority.

In previous elections, it was possible for the extra seats to influence which coalition won power. That shouldn't be the case this time after the system was tweaked at the insistence of Germany's highest court — so other parties will also get extra seats, ensuring that the makeup of Parliament matches their percentage of the vote.

Once the votes have been counted, President Joachim Gauck will propose a chancellor to Parliament. That candidate needs to secure a majority of all lawmakers in the lower house to take office. If lawmakers fail to give a majority to one candidate in three tries, Gauck could appoint a minority government or dissolve Parliament.

Parliament is elected for a four-year term.