BERLIN — The center-left Social Democrats have won the biggest share of the vote in Germany's national election.

They narrowly beat outgoing Chancellor Angela Merkel's center-right Union bloc in a closely fought race that will determine who succeeds the long-time leader at the helm of Europe's biggest economy.

The Social Democrats' candidate Olaf Scholz, the outgoing vice chancellor and finance minister who pulled his party out of a long slump, said the outcome was a clear mandate to ensure they assembled a good, pragmatic government.

The Union bloc said it too would reach out to smaller parties to discuss forming a government, while Merkel stays as caretaker until a successor is chosen.

According to the Associated Press, there is no referee for the process of forming a new government and no set time limit. Parties hold exploratory talks to determine who they have most common ground with, and one combination of parties then moves on to formal coalition talks.

Those negotiations typically produce a detailed coalition agreement setting out the new government's plans. Once a coalition is ready, Germany's president nominates to the Bundestag a candidate for chancellor, who needs a majority of all members to be elected.

If two attempts to elect a chancellor with a majority fail, the constitution allows for the president to appoint the candidate who wins the most votes in a third vote as chancellor or to dissolve the Bundestag and hold a new national election. That has never yet happened.

Merkel and her government will step down from power until the Bundestag elects her successor — a process that is usually completed within six months.