I think, ideally, all campaigns should be publicly financed, which means only individuals can contribute to them and that no one person can contribute more than $5. By checking the box on your tax forms saying you wish $3 to go to the election fund, you help to make that a reality. However, this is not the way the game is played currently, and the decision made by the Supreme Court would make publicly financed campaigns even less likely.
I do think it is ironic that President Obama is criticizing the decision made by the Supreme Court. Obama raised significantly more funds than McCain who ran a campaign based on public financing.
Overall, the world of campaign finance is fraught with contradiction. Geico, a company owned by known Democratic party supporter, Warren Buffet, gives large sums of money to the Republican party. Kohls department store and grocery chain gives large amounts of money to the Republican party despite the fact that one of their key shareholders, Sen. Herb Kohl (WI) is a Democrat. Then there is Anheuser-Busch, a company that gives a great deal of money to the Democratic party despite Cindy McCain being a major shareholder. This is the world of hedging.
Despite all the flaws with this practice, I still think it is better to have a paper trail, as it were, to show where the money is coming from. Granted, the more you know about the process, the less you want to swallow the product. Politics is a giant meat grinder, after all.
I have heard many on both sides of this issue cite the First Amendment of the United States Constitution which reads as follows:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances
I guess I don't really see how this can be used to defend the unchecked donations of large amounts of money from corporations and labor unions to political candidates. I was always taught that the First Amendment applied to individuals, not corporations. To what extent a corporation represents their employees or shareholders, or for that fact a labor union, is really up for grabs.