Top Republican super PAC donors backing Romney

Geier, 77, a veteran advertising man, gave $100,000 to the pro-Romney group after previously donating $250,000 as well as giving $500,000 to Rove's group. He is chairman emeritus of the New York-headquartered Geier Group, a global media company. Geier was a campaign bundler for Sen. John McCain's 2000 presidential campaign and has given to the Republican National Committee, as well as to GOP leaders like Sen. Mitch McConnell of Kentucky and Sen. Marco Rubio of Florida.

Perenchio, 81, gave $500,000 and has donated $3 million to Rove's group since 2010. He is a former chairman for the Spanish-language Univision television network. He was a top bundler for McCain's 2008 presidential campaign. Perenchio, who heads Chartwell Partners LLC, gave $10,000 last year to the National Republican Congressional Committee and $5,000 to the re-election campaign of House Speaker John Boehner.

In 2004, Perry was the largest single donor to the Swift Boat Vets and POWs for Truth, giving nearly $5 million to the tax-exempt organization. The group, composed of Vietnam War-era Navy veterans, was blamed for misleading attacks on Democratic presidential candidate John Kerry's service as a Swift Boat officer in Vietnam. Perry also gave $3 million that cycle to the Progress for America Voter Fund, another group supporting Bush.

When Texas Gov. Rick Perry — he is no relation to Bob Perry — entered the Republican presidential race in 2011 against Romney, Perry at first supported his home state candidate, giving $100,000 to a super PAC supporting the Texan's candidacy. But as Rick Perry's campaign faltered, Bob Perry shifted his allegiance to Romney. He gave $1 million last year before his massive $3 million donation last month.

Others who gave to the group supporting Romney:

—Kenneth C. Griffin, 43, a top hedge fund director, gave $100,000 to Restore Our Future after donating $100,000 earlier along with $300,000 to Rove's group last year. Griffin heads the Chicago-based Citadel Investment Group and was a McCain bundler in 2008. Last year, he gave $38,000 to the RNC and $22,500 to the National Republican Senatorial Committee, as well as thousands more to GOP candidates including Rep. Eric Cantor of Virginia and Sen. Scott Brown of Massachusetts.

—Harold Simmons, 80, gave $100,000 following an earlier $100,000 donation in January. He also gave $100,000 last month to Winning Our Future, the super PAC supporting Gingrich; his wife, Annette, gave $1 million to the Red, White and Blue Fund. A billionaire, Simmons was the top benefactor for Rove's group, providing $12 million between his personal checkbook and the coffers of Texas-based Contran Corp., a holding company with interests including chemicals and waste management.

Simmons rivaled Perry as a $4 million contributor to the Swift Boat group in 2004 and was a bundler for the Bush and McCain presidential campaigns. In addition to his $12 million donation to Rove's group, Simmons has also given more than $200,000 to GOP candidates and party PACS and groups.

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