Four months after Barack Obama first announced for president in 2007, Steve Lerner hosted a fundraiser for the Illinois senator at his Chapel Hill home.

He’s been raising money for Obama ever since.

Building on the fundraising base he helped start five years ago, Lerner has raised more than $137,000 for Obama’s re-election campaign. He and other so-called “bundlers” have helped the president raise more than $7.6 million in North Carolina since early 2011.

Republican Mitt Romney, meanwhile, has raised $5.8 million from North Carolina donors, according to reports filed with the Federal Election Commission. The figures don’t include contributions to so-called Super PACs that back the candidates.

Since Romney effectively won the nomination last spring, Obama has outraised him by around $600,000 in the state, according to an Observer analysis of contributions to the two campaigns.

Through September:

• Obama’s fundraising strength has come from the Triangle. He raised about $2.7 million from the Raleigh-Durham-Chapel Hill area, roughly $1.6 million more than Romney has.

• Romney rode fundraisers at Myers Park Country Club and the Duke Mansion to a wide edge among Charlotte donors, who gave him more than $1.2 million. Obama raised about $800,000 from Queen City contributors.

• Obama enjoyed an advantage among health care professionals and lawyers. Doctors and others in the field contributed $1.1 million to Obama compared with $490,000 to Romney.

• Lawyers contributed more than twice as much to Obama than Romney.

• Romney’s support has come from bankers and others in the finance industry as well as business owners.

• Romney’s donors tend to be fewer and bigger. Obama, with an aggressive Internet fundraising campaign, has more donors giving smaller amounts.

Obama’s North Carolina money came from 66,000 donations. Romney’s came from about 13,000 donations.

Polls show Romney lead

Both campaigns continue to fight for North Carolina even as polls show Romney with a consistent lead. On Wednesday the RealClearPolitics poll average showed the former governor up by nearly 6 points, and CNN shifted the state from tossup to “lean Romney.”

But the Obama campaign says early-voting numbers are promising for the president.

Both sides see fundraising as a reflection of enthusiasm.

“We’ve been incredibly successful in North Carolina,” said Dave Phillips, a High Point furniture executive and Romney’s state finance chair.

Lerner said Obama has built on the network that started in 2007.

“The biggest reason (for the advantage),” he said, “is that we’ve been doing it longer and we had carryover lists of names that date back to ’07 and ’08 who are still very enthusiastic about him.”

Lerner bundles donations for Obama. According to a list released by the Obama campaign and catalogued by the Center for Responsive Politics, Obama’s bundlers also include former textile executive Crandall Bowles of Charlotte, who raised $537,000.

Most North Carolina bundlers for Obama are from the Triangle. One, Amy Tiemann of the software company Red Hat, raised $474,000. John Replogle, CEO of a “green” cleaning products firm called Seventh Generation, raised $248,000.

Income matters

In Mecklenburg County, donations to the candidates fell largely along income lines.