The New York Times reports that Chicago media entrepreneur Fred Eychaner appears to be the largest single donor to liberal outside groups, giving a total of $14 million over the course of the election.
On the conservative side, Sheldon Adelson and his wife "contributed close to $92 million to super PACs,
which must disclose their donors. Millions more reportedly went to
tax-exempt political groups that do not have to disclose their donors,
bringing the family's total to well over the $100 million he had vowed
to spend to help Republicans this year."