5. Hedge-fund manager S. Donald Sussman donated over $27 million to Democrats in 2018.

Total donations: $27,545,500

Party Affiliation: Democrat

Net worth: Unknown

Donald Sussman is the founder of Paloma Partners. The Fort Lauderdale-based hedge fund was the top donor to Hillary Clinton's 2016 presidential campaign, giving $21.6 million, according to The Guardian.