No. 3 (tie): Jon Stryker, 54, a Michigan philanthropist.
Total: $2.066 million
Stryker has given $2 million to the Priorities USA Action super PAC and has given $66,000 in contributions to Obama and the Democratic Party. Stryker is the heir to namesake Stryker Corp., the major medical-device and equipment manufacturer. Stryker has been active in politics before the 2012 election; he contributed millions to help Democratic candidates statewide. And he also has given nearly $250 million of his personal wealth to groups supporting gay rights and the conservation of apes.
No. 5: Steve Mostyn, 41, a Houston-based personal injury attorney.
Total: $2.003 million
Mostyn has given more than $2 million to the Priorities USA Action super PAC that's helping Obama. Mostyn, the former head of the Texas Trial Lawyers Association, is a major backer of Democratic candidates in the state. He's also sank cash into a Texas political committee that tried unsuccessfully to unseat Gov. Rick Perry two years ago. Most famously, in 2009, Mostyn demanded tens of millions of dollars for property owners affected by Hurricane Ike in claims against the Texas Windstorm Insurance Association.
These rankings by The Associated Press, based on campaign financial reports submitted to the Federal Election Commission, include contributions to super PACs, presidential campaigns, political parties and joint-fundraising committees that help Obama. Federal law limits maximum contributions to campaigns, parties and affiliated committees, but federal court rulings have stripped away such limits on super PACs. This analysis excludes secret-but-legal contributions that might have been made to nonprofit groups, which can pay for so-called issue ads that don't explicitly advocate for or against a candidate. Such groups are not required to identify their donors.
Where available, the analysis considered donations "bundled," or raised, from other wealthy donors for Obama or Republican nominee Mitt Romney. Obama periodically identifies his bundlers, although Romney has resisted repeated calls to do the same.