While the popular Merkel is a virtual shoo-in for another four years as leader, the last opinion polls before the election showed her hopes of forming the coalition she wants are hanging by a thread. [break]
Merkel hopes to ditch the current "grand coalition" government between her conservatives and the center-left Social Democrats, in favor of an alliance with the pro-business Free Democrats.
But her lead has shrunk in recent weeks and a poll by the Forsa institute published just two days before the vote showed her preferred coalition on 47 percent -- not necessarily enough to clinch a clear majority under Germany´s complex electoral arithmetic.
And with pre-election opinion polls historically imprecise and other surveys showing that around one quarter of Germans were still undecided as they head to the ballot box, all parties campaigned hard until the last moment.
Whichever coalition emerges victorious from Sunday´s vote faces a bulging in-tray of challenges, with the country poised for its biggest slump in output in 60 years and at odds over an increasingly bloody mission in Afghanistan.
Security was tight throughout the country on election day in the wake of a series of threatening messages from Islamic militants, including one from Al-Qaeda chief Osama bin Laden.
Overall, 62.2 million people were eligible to vote for 29 parties vying for power. Election-day weather is forecast to be dry and sunny across the country, according to the German weather service.
Preliminary exit poll results are expected around 1600 GMT.
Related story
Four ways Nepalis overseas could vote — EC begins pilot for Mar...
