It can't justify taxing some people for the benefit of others. The majority has no more right to rob the minority than to exterminate it. The more excessive the powers of government, the more bitter elections are bound to be. If government were limited to a few modest powers, the stakes in any election would be small, and it wouldn't be worthwhile to spend huge sums of money to help one candidate win. Those who demand campaign finance reform are approaching the problem from the wrong end.
Big government creates pressure for lavish campaign spending.
Limited government doesn't. Our liberty should never depend on who wins an election. Unfortunately, this is far from the case. In fact both major parties now stand for predatory government. When your real problem is constitutional, you can't solve it by improving methods of counting votes.