Merkel looks likely to end up leading either a "grand coalition" government with the center-left Social Democrats of defeated challenger Peer Steinbrueck â¿¿ reviving the alliance that ran Germany in her first term â¿¿ or, less likely, with the environmentalist Greens.
Either way, several weeks of difficult negotiations are expected.
"The ball is in Merkel's court," said Steinbrueck, a former finance minister under Merkel who has said he won't serve under her again. "She has to get herself a majority."
"Angela Merkel is stronger than ever, also in her party," said Manfred Guellner, the head of the Forsa polling agency. "But governing is going to be odd because she will have to form a 'grand coalition' although she is only a few seats away from an absolute majority."
Merkel's conservatives finished far ahead of Steinbrueck's Social Democrats, who won 25.7 percent of the vote â¿¿ not much better than the post-war low of 23 percent they hit four years ago.
Their Green allies polled a disappointing 8.4 percent, while the hard-line Left Party scored 8.6 percent. But although the three parties on the left together hold a thin parliamentary majority, there's virtually no chance of them governing together.
The Left Party includes heirs of East Germany's former communist rulers, opposes German military deployments abroad and is the only party that voted against Merkel's policies of bailing out debt-troubled European countries in exchange for reforms. The two center-left parties on Sunday renewed promises not to form an alliance with the Left.
"We did not achieve the result we wanted," Steinbrueck told supporters, insisting he wouldn't engage in "speculation" about the next government.
Merkel's conservatives, the Social Democrats and Greens "have largely similar positions" on Europe, said Oscar Gabriel, a political science professor at Stuttgart University. He noted, however, that "there are a few nuances," with the center-left parties more open to limited pooling of European countries' debt something the chancellor has refused to countenance.