A number of states provide tax incentives for making campaign contributions. From a purely naive view point this feels like a waste since in theory (emphasis on theory) if we assume roughly equal political beliefs in a population the campaign contributions would be roughly equal on each side and 'cancel out' each other, not having a large effect on actual politics but costing the government on tax income.
This is very naive, as I'm sure one political party or another actually ends up benefiting more from the campaign contributions. Which party benefits would largely be a matter of which way the citizens of state with incentives lean on average. I could imagine giving a tax incentive could be a way for the party that expects to get more from an incentive in their state to strengthen their parties local and national position by getting more campaign donations, though that seems kind of cynical.
Still, has there been a more detailed analysis of this sort of policy? What are the stated (and actual) goals for giving incentives, and which parties are generally benefiting from them?
In addition, has any study suggested what the affect of removing these incentives would be? IE, how much would each party lose in campaign contributions and what would be the the final net affect on percentage of campaign finances available to each political party (ie, does one party really gain a noticeable benefit)? What are we loosing in taxes relative to this change in political campaigning? Are any social, ethnic, or other demographics getting noticeably more or less political power as an affect of the incentives?
I'm mostly interested in statistics if actual studies exist. Of course it's possible no one has actual statistics so I'm happy to take what I can get :)