Voting began Sunday in Germany's general election, with opinion polls suggesting Chancellor Angela Merkel's ruling coalition may lose its parliamentary majority.
Merkel, leader of the center-right Christian Democratic Union, is expected to remain chancellor for a third term, but she may have to ditch her current coalition partner, the Free Democratic Party, if it polls badly. She would then have to form a new government with a more leftist bent.
Polling stations close at 6 P.M. local time (1800 GMT) Sunday. Some 61.8 million people are eligible to vote. As many as a quarter of all votes are likely to have been cast in advance and sent in by mail.
Media outlets are not allowed to broadcast exit-poll results until voting is over. Unless the race is very tight, the outcome is likely to be clear within an hour or two of closure, using calculations from exit polls and the subsequent vote-count projections.
Provisional final results are expected in the small hours of Monday.
Pollsters say the CDU and its Bavarian Christian Social Union ally are likely to again win the biggest share of votes, about 40 percent, but support for the FDP will slump from 15 percent four years ago to about 5 percent.
That may not suffice for a parliamentary majority, prompting Merkel to turn instead to the opposition Social Democrats who formed a so-called "grand" coalition with her during her first term as chancellor. The center-left SPD are expected to come a distant second with 26-28 percent.
Merkel has hinted she is ready for a grand coalition of the two big parties, but has avoided explicitly saying this is Plan B.
The SPD candidate for chancellor, Peer Steinbrueck, has refused to concede his impending defeat. He has been praised for reviving the demoralized party, which won only 23 percent of votes at the last election in 2009.
Turnout, which slumped to 70 percent in 2009, will be decisive.
In 2009, the SPD proved to be the main casualty, with its absolute number of votes falling by 6.3 million, whereas the CDU/CSU got only 2 million fewer votes than in 2005, giving it a net advantage.
Even with support from the Greens, expected to win under 10 percent, the SPD is unlikely to draw even with the CDU/CSU this time.
Steinbrueck has said he will not serve as a minister under Merkel, but aides have hinted that he wishes to lead any delegation negotiating on a coalition.
A state election is being held in parallel in Hesse state, the region around the banking and transport hub of Frankfurt. An alliance of the SPD and Greens is running neck and neck with the state's incumbent CDU-FDP government.
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