By Michelle Martin BERLIN (Reuters) - Germans voted on Sunday in an election expected to hand Chancellor Angela Merkel a third four-year term, but she may be forced into an awkward coalition with her leftist rivals following a surge in support for a new anti-euro party. Europe is closely watching Germany's first national election since the eruption of the euro zone debt crisis in 2009. Some hope Merkel will take a softer stance on struggling euro states such as Greece if she is pushed into a so-called grand coalition with the Social Democrats (SPD). ...