Former President Bill Clinton attends a fundraiser in support of Anthony Brown, left, for governor and Ken Ulman for lieutenant governor at the Bolger Center in Potomac, Md. (Jonathan Newton/The Washington Post)

Former president Bill Clinton touted Maryland gubernatorial hopeful Anthony G. Brown as the candidate best positioned to build on the state’s successes at a fundraiser Tuesday night in Potomac that organizers said pulled in more than $1 million for Brown’s campaign.

“I know what is in his mind, I know what is in his heart, and I know what his abilities are,” Clinton told a crowd of about 700 gathered in a white tent on the rolling grounds of the Bolger Center, a conference center in the home county of Brown’s two main Democratic rivals.

Aides to Brown, the current lieutenant governor, said the event brought in his largest single-day haul since his campaign launched about a year ago. Donors, who contributed up to $4,000 to attend, sipped wine and cocktails and nibbled on Swedish meatballs and other hors d’oeuvres as they awaited Clinton’s arrival. When the former president took the stage, a sea of smartphones rose above the crowd.

Clinton, who endorsed Brown last month, said he had come to be part of Brown’s “brigade” for two reasons.

“I do admire and feel enormous affection for Anthony Brown,” Clinton said. “The second reason is I think it’s important, when people have got a deal that’s working, to build on it and not reverse it.”

He went on to praise the work of Gov. Martin O’Malley (D), Brown’s boss for the past 71 / 2 years and a potential 2016 presidential rival for Hillary Rodham Clinton. O’Malley was among the speakers Tuesday night at the event, which also drew several other elected officials who have endorsed Brown as well as members of the Annapolis lobbying corps, apparently aiming for good relations with someone who could be the next governor.

Brown faces Attorney General Douglas F. Gansler and Del. Heather R. Mizeur (Montgomery) in the June 24 Democratic primary in the race to succeed O’Malley, who is term-limited.

In his remarks, Clinton addressed head-on Brown’s largest political liability: the dismal launch of Maryland’s online health insurance marketplace. Among Brown’s responsibilities under O’Malley has been overseeing the implementation of the federal health-care overhaul in the state.

Clinton said that candidates are strengthened by mistakes and that it was a credit to Brown that he had worked to fix the problems Maryland experienced.

“Anthony, I have been in your brigade since the first time I met you,” Clinton told Brown, a reference to Brown’s frequently touted military service.

Aides said Brown struck up a friendship with Clinton in 2000, when the then-president attended a signing ceremony in Annapolis for a Maryland gun-safety law as part of an effort to highlight state actions on that issue. Brown was a state delegate representing part of Prince George’s County at the time.

In 2008, Brown endorsed the presidential bid of Hillary Clinton and traveled to several states to campaign on her behalf, attending events with both Clintons.

Gansler often talks on the campaign trail about his decision to endorse President Obama in the 2008 primaries and co-chair his campaign in Maryland.

In a statement last month, Gansler said he has a “tremendous amount of respect” for Bill and Hillary Clinton.

“Let me make clear that when I am governor, I will be strongly supporting Hillary Clinton for president, should she choose to run,” Gansler said.