While several white Southern Democrats in culturally conservative districts are keeping Sen. Barack Obama (Ill.) at arm’s length, Rep. John Barrow (D-Ga.) is wrapping both arms around the presumptive Democratic presidential nominee and holding tight.

Barrow’s campaign has made much of Obama’s endorsement, and last month Obama cut a radio ad for the sophomore Congressman who endorsed his presidential primary bid back in February.

The reason for Barrow’s enthusiasm for Obama almost certainly has to do with the fact that 45 percent of his district is black, which means that half the primary electorate could be black. But it probably also means that the Congressman, who came fewer than 1,000 votes away from losing his seat to a Republican in 2006, believes his tougher challenge this cycle lies in the July 15 Democratic primary rather than the November general election.

Early this cycle, Republicans were keen on finding a top recruit who could knock off Barrow after very nearly accomplishing that feat in 2006. For much of last year their hopes appeared to rest on orthopedic surgeon and Lt. Col. Wayne Mosley (R), who has served four tours in Iraq and Afghanistan and was seen as a top recruit. But after Mosley opted not to run in December, Republican excitement over the seat appeared to wane.

But then, just before Georgia’s April filing deadline, state Sen. Regina Thomas, who is black and has served in the Georgia General Assembly for a dozen years, filed to challenge Barrow in the Democratic primary. Suddenly, Republicans were giddy that Thomas might be able to knock off Barrow and take his massive war chest and tough political machine out of the equation before the general election campaign even began.

But besides a radio ad in the Augusta region and plans to drop another radio and cable television ad in Savannah this week, Thomas has been running a fairly quiet campaign.

Thomas had not yet filed a pre-primary Federal Election Commission report by Monday afternoon, but she estimated that she had raised about $42,000 for her Congressional campaign and had $25,000 on hand.

By contrast, according to his recently filed FEC report, Barrow raised $265,000 between April 1 and June 25, spent more than $553,000 during that time and still had more than $1 million in cash on hand. Barrow has run two television ads on broadcast TV district-wide and he’s picked up support from several prominent black leaders in the state legislature, including every black state legislator from the Augusta region.

Still, simply by virtue of the racial makeup of the district, Barrow has to be worried.

“I think [Thomas] does have some chance,” said Charles Bullock, a University of Georgia political science professor. “This is one of those contests that’s hard to get a handle on because she’s certainly not that visible, but she could conceivably pull off an upset. And the way she would have to do it, since she doesn’t have any money, is to mobilize the support of black political figures and ministers across the district.”

But the clock is ticking.

While pundits may see her campaign as a low-key affair, Thomas said Monday that her Congressional bid is being run in the exact same grass-roots style that has made her success in her Savannah-based state Senate district.

Thomas said she’s not concerned about pushing her endorsements out to the media in the final days of the campaign.

“A lot of the local officials I do know are supporting Barrow, but that’s OK,” Thomas said. “My endorsements [show] at the time when people vote.”

One interesting donation Thomas has received came in the form of a $250 check from fellow state Sen. Eric Johnson, a Republican who serves as President Pro Tem of the Senate. The donation sparked speculation that Republicans were getting behind Thomas’ campaign because they considered her the easier candidate to beat in the fall.

Johnson said Monday that people shouldn’t read too much into his small campaign donation. He said the check to his longtime Senate colleague was “a friend supporting a friend” and vowed to vote for the Republican nominee in the fall.

Thomas said that if Republicans had any involvement in the Democratic primary it would probably be to ensure Barrow is the one who makes it to the general election.

“I would think they would want Barrow to stay there because he’s been voting with Bush and Republicans,” she said.

As for Obama’s endorsement in the primary, Thomas said the incident has actually benefited her campaign.

“People understand it was a quid pro quo kind of thing,” Thomas said. “By Barrow being a superdelegate and giving his vote to Obama, Obama had to respond by doing a favor for Barrow. People understand that type of politics. … People are tired of the status quo. They want to move away from name dropping and name calling, they want to see what the candidate brings to the table.”

The Republican primary is currently a three-way race, but the leading contender appears to be John Stone, a radio personality and former Congressional aide to the man who Barrow beat in 2004 and 2006, former Rep. Max Burns (R). Indeed, Republican leaders appear to be signaling that they want Stone in the general election; recent FEC reports show that House Minority Leader John Boehner (R-Ohio) cut Stone a $5,000 check from his political action committee in mid-June.

Republican officials have also continued their attacks on Barrow’s voting record.

“John Barrow has been a leader for nothing more than the Democratic leadership’s liberal policies,” National Republican Congressional Committee spokesman Ken Spain said on Monday. “While his support for massive tax hikes and soaring energy costs might earn him kudos from his Washington allies, Georgia voters are undoubtedly feeling the financial impact of his policies on their pocketbooks.”

But Democratic Congressional Campaign Committee spokeswoman Kyra Jennings said party leaders are confident about Barrow’s chances both next week and later this fall.

“With Congressman Barrow’s leadership for his district and the enormous Republican recruitment failure here, Congressman Barrow is the strongest candidate in this race and is in a great position to win re-election in November,” Jennings said.