People are over-analysing the importance of sports on election results. I'm not sure wich is more silly, people thinking Scotland will vote for indipendance because they host a non-important sport-event the same year, or people thinking a Milan win will make people vote for Silvio.
Is there any election in the past 50 years in a Western Democracy that's is believed to have been determained by a single sports event?
In the 1970 UK general election, there was a last-minute swing from Labor to the Conservatives, who ended up winning; it's thought that this is because the election took place shortly after England lost a significant match to West Germany during the 1970 World Cup (furthermore, it's thought England only lost because goalkeeper Gordon Banks was forced not to play due to a stomach illness).
Sometimes history rests on the seemingly insignificant.
