Del. Jolene Ivey (D-Prince George’s) speaking on the first day of the Maryland legislative session in Annapolis in January. (Marvin Joseph/The Washington Post)

Maryland’s three major Democratic gubernatorial hopefuls each could claim at least one “first” if elected: Lt. Gov. Anthony G. Brown (D) would be the state’s first African American governor. Del. Heather R. Mizeur (D-Montgomery) would be the nation’s first openly gay governor, plus the state’s first female governor. Attorney General Douglas Gansler (D) would be the first governor from Montgomery County.

Brown, who has been leading in recent polls, and Mizeur have downplayed who they are as they campaign for the state’s top office. Gansler’s campaign released a new radio ad Monday that features his running mate, Del. Jolene Ivey (D-Prince George’s), touting her chance at history — and slamming Brown for not being an early supporter of President Obama, the country’s first African American president.

“If elected, I’d be proud to be the first Democratic African American woman to serve as lieutenant governor in American history,” Ivey says in the 60-second ad.

Ivey praises Gansler’s record as attorney general and mentions some of the things they would do in office, such as increasing support for minority and women-owned businesses. Meanwhile, she says: “Anthony Brown worked to defeat Barack Obama when he first ran for president.”

Ahead of the 2008 presidential election, Brown endorsed Hillary Clinton over Obama, who was his classmate at Harvard Law School. The Clintons have been close allies of Gov. Martin O’Malley (D). Former president Bill Clinton endorsed Brown in April and attended a fundraiser for him in Potomac last month that organizers say garnered more than $1 million for Brown’s campaign.

Ivey also criticizes Brown for his role in the launch of the state’s online health insurance marketplace, which crashed on its first day and is being replaced using technology from Connecticut. Brown is in charge of implementing Obama’s Affordable Care Act in Maryland, a task that he says did not include day-to-day oversight of construction of the exchange.

Gansler has hammered Brown on this issue on the campaign trail, but in the radio ad Ivey connects that failure to the president: “And this year, Brown mismanaged Obamacare, hurting the president and costing thousands in our community access to health care. Doug Gansler and I will continue to back the president and fight for you every day.”

Brown campaign manager Justin Schall said in a statement Monday morning: “Doug Gansler and Jolene Ivey are two desperate and irresponsible candidates who are more than 20 points behind in the polls and will say anything to get elected. Voters see through these reckless negative attacks.”