[sgt101]

I think you are thinking that elections are a zero sum game, but the reality is that most people either don't vote, always vote for a party no matter what or vote for the candidate that they know. Politicians are all about influencing the swing vote - get people who never vote to vote for you or alternatively influence some small part of the electorate that does make positive decisions. Most people who don't want the stadium will either not vote or vote the way that they would have anyway, the calculation is that voters who are "fans" will vote positively for the people who stick up for their team. Stir in the "I'll vote for the person who's popular" block (which politicians are hoping that the free exposure in the stadium campaign will grant) and the negative effect of shutting out your opponent (because backing like this is strangely exclusive for some reason).