WASHINGTON — The most significant “super” political committees in this year’s presidential campaign revealed the names of their wealthy donors Tuesday. The casino mogul who, with his wife, contributed

$10 million to Newt Gingrich’s group, gave five times more than the group collected from all other sources.

The new financial reports, which offered a detailed accounting of money collected and spent by super PACs, underscored how millionaires and billionaires are influencing the presidential election behind the scenes.

The group supporting Mitt Romney, Restore Our Future, said it collected $17.9 million in contributions since July, most of which it spent on advertisements supporting Romney or attacking Gingrich. The top four donors to the group were hedge fund managers. The pro-Romney group waited to file its report until hours after Romney was projected the winner in Florida’s important GOP primary, just ahead of the midnight deadline.

Casino mogul Sheldon Adelson and his wife, who collectively gave $10 million this month to the pro-Gingrich group, Winning Our Future, were not listed in the latest filings because the reporting period covered 2011. But the group’s reports showed only $2 million in donations, making the Adelsons by far the paramount backers in Gingrich’s Republican candidacy.

Adelson, a staunch advocate for Israel, was rewarded in Gingrich’s speech in Florida late Tuesday with a renewed promise by the candidate that, if elected, he would relocate the U.S. Embassy in Israel to Jerusalem. Adelson has long supported such a move.

American Crossroads, the Republican group backed by former George W. Bush adviser Karl Rove, said it raised $51 million along with its nonprofit arm last year. Most of its $11 million in contributions over the past three months came from roughly a dozen wealthy donors.

While most recent public attention has focused on super PACs spending major sums for negative TV ads assailing Romney and Gingrich, Tuesday’s figures are a sign of even greater spending to come in the

general election battle between the Republican nominee and Democratic President Barack Obama.

The super PACs’ war chests underscore the extraordinary impact the groups will have on this year’s race. In GOP primaries so far, groups working for or against presidential candidates have spent roughly $25 million on TV ads — about half the nearly $53 million spent on advertising so far to influence voters in the early weeks of the race.

Crossroads’ financial reports identify wealthy donors who had given contributions reaching as high as seven figures by the end of 2011. Among the largest contributors was Dallas businessman Harold Simmons, who gave the group $5 million in November and whose holding company, Contran Corp., donated an additional $2 million  Simmons is a major donor to GOP and conservative causes who pumped as much as $4 million into the “swift boat” campaign that helped sink Democratic presidential nominee Sen. John Kerry in 2004. Simmons, an early supporter of Texas Gov. Rick Perry’s presidential run, also was a fundraising “bundler” putting donations together for Arizona Sen. John McCain.