Maryland Attorney General Douglas F. Gansler. (Cliff Owen/AP)

Maryland Democratic gubernatorial hopeful Douglas F. Gansler and his running mate made their candidacies official Thursday, filing for office at the State Board of Elections two hours before the current governor was scheduled to give his final State of the State address.

Gansler, the state’s attorney general, and Del. Jolene Ivey (D-Prince George’s) said they had chosen Thursday morning to file because it is the 50th anniversary of the 24th Amendment to the Constitution, which prohibited states from enacting a poll tax.

The pair also used the occasion to propose the expansion of early voting on Saturdays, arguing that doing so would boost turnout among voters who can’t get away from work during the week. Under current law, as part of a week of early voting, Maryland opens a limited number of voting centers on one Saturday before the election. Under Gansler’s plan, all polls across the state would be open on the Saturday immediately preceding the Tuesday voting.

“The success of our democracy hinges on voting, but the United States ranks dead last in voter turnout among G-8 nations,” Gansler said. “For too many Marylanders, work, child care and transportation are obstacles to exercising this basic right. That’s why Jolene and I are proposing to expand early voting to open all polls on the Saturday before Election Day.”

The ticket also released the latest installment of its “Front and Center” video series, focusing on their voting proposal.

Gansler’s campaign did not provide a cost estimate for the plan, but state election officials have estimated that fully opening polls for another day would cost at least $10 million, and they have said that the state would incur additional costs transitioning to another full day of voting.

Gansler said he envisions his plan taking effect after this year’s elections.

“I think it’s too late to have it in place for this cycle,” he told reporters.

Gansler announced his candidacy in late September, but like most contenders, he was seeking to draw a second round of attention to his bid with his official filing.

Gansler faces Lt. Gov. Anthony G. Brown and Del. Heather R. Mizeur (Montgomery) in June’s Democratic primary. Both have already filed for office.

Gov. Martin O’Malley (D), who is prohibited from running for a third consecutive term, is scheduled to deliver his eighth and final State of the State address at noon Thursday.