ANNAPOLIS, Md. (AP) — The running mate of a Maryland gubernatorial candidate who died suddenly last week announced shortly before a Thursday deadline that she will run for governor in his place.

Valerie Ervin had three options: Run herself in a crowded Democratic primary, choose someone else to lead the ticket, or scrap the campaign altogether. With a 5 p.m. Thursday deadline looming, Ervin chose to pick a running mate and compete herself.

"I believe in a Maryland where working families come before corporate profits, where we help every kid achieve their full potential, and we all can thrive regardless of where we were born, the color of our skin, or the size of our bank account," Ervin said in a statement announcing her candidacy.

She chose Marisol Johnson as her running mate, describing her as an immigrant from El Salvador who owns a small business, is a mother of four, and was a former Baltimore County school board member. Ervin is a former two-term member of the Montgomery County Council in the state's most populated county.

Ervin, also a former director of the Center for Working Families, which is part of the Baltimore-headquartered Annie E. Casey Foundation philanthropy, is now one of seven candidates vying for the Democratic nomination in the June primary to oppose Republican Gov. Larry Hogan this fall.

Prince George's County Executive Rushern Baker and former NAACP head Ben Jealous are among those seeking the Democratic nomination to challenge Hogan, the popular Republican incumbent.

Before Thursday's announcement, Ervin gave no hint as to whether she might take over the top of the ticket or make another decision following the sudden death of candidate Kevin Kamenetz, which redrew Maryland's political landscape.

Kamenetz's death from a heart attack at 60 shocked everyone in the state's political circles. The county executive of Baltimore County was widely perceived as one of the top three Democratic contenders in the race. With a $2 million war chest, he certainly had the most money of any Democratic hopeful.

Donald Norris, a political analyst and professor emeritus of public policy at the University of Maryland Baltimore County, described the death of a major candidate weeks before a primary as "unprecedented" in state politics.

"I don't recall anything like this at any level, but certainly not at the level of the governor or any statewide office," Norris said Thursday.

In recent days, some Democrats have publicly urged Ervin to find a running mate and keep the campaign moving.

Donna Edwards, a former Democratic Maryland congresswoman and a candidate for Prince George's county executive, recently tweeted her support for Ervin as governor, saying "there's no one better to carry on Kevin's legacy."

Ervin's campaign website was launched Thursday afternoon to coincide with her announcement. She says she wants to provide universal health care for all Maryland families, make the state's public schools the best in the nation, and help lead the country to becoming 100 percent reliant on renewable energy.

Come the June 26 primary, if voters want to back Ervin and Johnson's campaign, they will have to choose the box for Kamenetz and Ervin. The ballots for the primary are already printed and ready to go.

Ervin said she has sought legal advice about what campaign funds she might be able to use from the previous campaign, but she said she decided to run regardless of how much money she could raise.

"We know how to build a grassroots effort, and people are really waiting on me to do something like that," Ervin told reporters at the state elections board.