BERLIN (Reuters) - More than 1,500 police will be on duty in Berlin on Sunday, when Germany s capital faces the logistical challenge of organising an election expected to draw a large turnout - while ensuring its annual marathon also runs smoothly. Police, election officials and race organisers have been in close consultations about security arrangements, especially following a deadly truck rampage on a Berlin Christmas market last December as well as an attack on the Boston marathon in 2013. Officials with the Berlin police and the BKA Federal Criminal Police Office said they had no indications of any specific plots to attack either the race or the city s 1,779 polling stations. Berlin s state election office said letters had been sent to around 44,000 of the city s 2.5 million eligible voters warning that some 30 stations might be difficult to reach because of the marathon.  The marathon is expected to end in early afternoon, while polls close at 6 p.m. local time. Voter participation is expected to exceed the 72.5 percent of 2013 largely due to a referendum about the fate of Berlin s Tegel airport that served the city through the Cold War.  Voter participation was already relatively high in 2013, but we think it will be even higher this year because of high interest in the Tegel referendum,  a spokesman said.  