One of the GOP’s biggest financial backers has changed presidential horses.

Again.

Texas billionaire Harold Simmons donated $100,000 to a super PAC supporting the presidential bid of former Massachusetts Gov. Mitt Romney in January, according to a fundraising report released Monday afternoon.

Simmons has now donated money to just about every Republican candidate -- and super PAC -- involved in the 2012 Republican primaries.

Simmons got started last February with a donation to Rep. Michele Bachmann of Minnesota. In April, he gave money to former House Speaker Newt Gingrich's campaign. Less than two weeks later, he sent a check to Tim Pawlenty, the former Minnesota governor.

In June, he gave to Romney, who received a $2,500 donation from Simmons. Less than a week later, he sent a check for $100,000 to a political group supporting his home state governor, Texas Gov. Rick Perry.

The next month, he sent a check to Rep. John Thune, a South Dakota Republican who never even got in the race. Sen. Mark Rubio (R-Fla.), tipped as a possible vice-presidential nominee, received a donation from Simmons in August.

When Perry formally entered the presidential race, Simmons gave him the legal maximum of $2,500.

After Perry dropped out of the race, Simmons switched to the surging Gingrich in December by donating $500,000 to a super PAC backing the former House speaker.

A month later, Simmons is back with Romney.

At the end of the day, it may not matter which Republican candidate has Simmons's backing.

Simmons simply wants to beat President Barack Obama. He has already donated more the $5 million to an independent campaign entity called American Crossroads that plans to spend as much as $300 million to defeat the president and other Democrats.

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