Out-of-state money bolstered the fundraising of U.S. Sen. Bill Nelson as he outpaced all of his 2012 Republican challengers in fundraising during the third quarter.

It remains to be seen how the dollar-collection part of the election contest will match up now that Congressman Connie Mack, R-Fort Myers, is jumping into the race.

For political experts, Nelson’s campaign cash numbers are no surprise, given the senior senator’s Beltway connections and decades of name recognition.

“It’s sort of the nature of being an incumbent senator,” said University of Central Florida political science professor Aubrey Jewett. “You’re going to have access from all around the country and particularly from all the well-heeled interest in D.C.”

Overall, Nelson, who has raised $5.3 million for his re-election effort, picked up nearly $1.9 million in the third quarter of 2010.

The GOP’s three top contenders -- Mack joined after the third-quarter numbers were in -- barely topped the $1.2 million mark combined in the same quarter.

Former state House Majority Leader Adam Hasner of Boca Raton raised $535,000 in the quarter; former U.S. Sen. George LeMieux posted $403,000; former Ruth’s Chris Steakhouse CEO Craig Miller brought in $226,000; and Plant City businessman Mike McCalister accumulated $71,000.

While it is unknown if potential donors may be holding back, waiting for the primary process to determine the GOP candidate, Jewett said he expects the party’s nominee will get large national backing.

Now that Mack has entered the race, there is also the chance that the party’s candidate will be familiar with fundraising on the national level.

In 2010, Mack raised $963,782 as he defeated two underwhelming candidates in the general election in his congressional district.

When he first took the federal seat, in 2004, Mack drew $1,892,757.

As for Nelson, besides donations from some of his historically biggest contributors, including Comcast, Greenberg Traurig, Kindred Healthcare and Carnival Corp., a few notable names round out the donor list: former Democratic presidential candidate Michael Dukakis and Baltimore Orioles owner Peter Angelos.

Overall, Nelson picked up $796,268 in contributions from Florida residents, companies and organizations, while his campaign coffers grew by $983,381 from non-Floridians, according to information posted by the Federal Election Commission.

The Orlando Democrat picked up $774,768 from 988 Floridians and $646,512 from 571 people whose primary residences are in another part of the country.

Meanwhile, a vast majority of his contributions from corporations originated closer to the Beltway, with 182 of his 199 corporate contributions coming from outside of Florida.

Of the $358,369, Nelson received from groups and businesses that all fall under the FEC’s corporation category, all but $21,500 came from outside the state.

Jewett said he didn’t see Nelson having a problem with business in Florida, any more than any other Democrat. Jewett added that there aren't a huge number of Fortune 500 companies based in Florida “for a state our size.”

Florida Atlantic University assistant political science professor Kevin Wagner said that just because a business isn’t headquartered in Florida doesn’t mean they are uninterested in the state.

Atlanta-based Bank of America gave $10,000; Philadelphia-based Comcast donated $5,000; Arlington, Va.-based Lockheed Martin PAC contributed $3,500; and Walt Disney Production employees, $5,000.

“I'd say there are a few things going on. The first is that corporations are usually headquartered (in) places that have favorable tax laws. That is why so many are in Delaware,” Wagner said. “Second, people and businesses with national interests often donate to senators and congressmen across the nation that they believe are supportive of issues with which they are concerned.