The financial sector is far and away the largest source of campaign contributions to federal candidates and parties, with insurance companies, securities and investment firms, real estate interests and commercial banks providing the bulk of that money.

The sector contributed generous sums to both parties until 2010 when donations began to heavily bias Republicans, which likely reflects the finance industry's interest in overturning the financial regulations from the Dodd-Frank Act, implemented to protect consumers from predatory lending practices and risky financial decisions from the industry. In 2014, the industry as a whole contributed half a billion dollars to candidate and party committees, PACs as well as outside spending groups; 62 percent of the funds given to candidates and parties went to Republicans. In 2012, the giving was even higher (as is the trend with presidential cycles) at $687,000; nearly 70 percent of the candidate and party gifts went to the GOP. [Read more Background]