Political clout in Washington, D.C., frequently depends on money. Seeking to promote their own agenda, interests such as political action committees (PACs), corporate and union representatives, and wealthy individuals use the lure of money—legally and illegally—to win access to key decisionmakers and gain their support on issues.

Campaign contributions are the most common way that money is used to influence politics. Each year, congressmembers receive hundreds of millions of dollars in campaign contributions. Regulated by federal law, these contributions can be considered illegal depending on the amount contributed, the source of the contribution, and how the money is spent.

Money is crucial to congressmembers who are seeking reelection. As of 1995, the average House of Representatives candidate spent approximately $440,000, while the average Senate race cost $4.4 million. According to senators and representatives, raising campaign contributions from constituents and other sources is a never-ending process that...