Las Vegas casino mogul Sheldon Adelson and his wife poured $33 million into "super" political action committees helping former GOP presidential nominee Mitt Romney in the final weeks of the election.
Adelson's family's contributions to two prominent pro-Romney super PACs bring his total giving in federal races to about $95 million this election cycle.
Those donations include $10 million to the Restore Our Future PAC and $23 million to the Karl Rove-backed American Crossroads PAC since mid-October.
Campaign finance filings are due to the Federal Election Commission on Tuesday and will detail how campaign organizations for Romney and President Barack Obama -- and a slew of super PACs -- raised and spent unprecedented sums of cash. That money was expected to push the presidential campaign's total cost past $2 billion.