Lt. Gov. Anthony G. Brown claimed victory in the Democratic nomination for governor Tuesday after early returns suggested a landslide win.

"It's about where we're going. It's about what next," Brown said in a victory speech as he led with three times as many votes as his closest competitor. He is positioned to become Maryland's first African-American chief executive.

In the Republican race, former Ehrlich administration official Larry Hogan accepted the GOP nomination after Harford County Executive David R. Craig, conceded defeat.

MORE: See the full Maryland primary election results

The primary victories set the stage for a spirited general election contest to succeed term-limited Gov. Martin O'Malley, who praised Brown as "a true American success story."

Despite being outnumbered in Maryland 2-1 by Democrats, Republicans hope that voters are fatigued by eight years of O'Malley and will elect a GOP governor instead.

Brown's win over Attorney General Douglas F. Gansler and Del. Heather R. Mizeur — both of whom conceded defeat shortly after 10 p.m. — was the result of a campaign promoted by more than $12 million and statewide name recognition.

Brown ran on a platform of building on O'Malley administration priorities. He promoted his plan to eventually expand half-day pre-K to all Maryland 4-year-olds and pitched himself as a competent leader who could make the state even better.

His stump speech relayed his biography as the son of immigrants, a Harvard graduate who attended the elite school on an Army ROTC scholarship and later served in Iraq. He invoked his background in his victory speech, telling supporters it was part of the American dream to seize opportunity.

"Together we campaigned with spirit, knowing each of us was part of something bigger," he said.

Hogan, in his victory speech, appealed to Gansler and Mizeur supporters to join his campaign, saying they had shown "they want change in our state."

He portrayed November's election as critical to reversing economic decline in Maryland. "This is a fight for Maryland's future, and it's a fight worth fighting," he said.

Brown's message resonated with Democratic voters, among whom O'Malley remains widely popular.

"I really wanted Anthony Brown because I like the direction Maryland has been going in so far," said Kandice Long, a 26-year-old teacher from Capitol Heights in Brown's home jurisdiction of Prince George's County. In early returns, Brown secured more than three-quarters of the vote there.

Brown has downplayed the historic nature of his campaign, and it wasn't until after Long cast her ballot that she learned he would be not only the first African-American governor in Maryland, but also only the third ever elected in the U.S. history.

"I didn't even realize he would be making history," Long said.

Gansler cast himself as a fighter taking on the state's Democratic establishment, and said he was dedicated to closing the state's achievement gap and improving the business climate.

In his concession speech, Gansler said he and Brown agreed on more than they disgreed.

"I'm a fighter," Gansler said. "We fell short today, not from a lack of hard work or dedication. … Tomorrow, after we shake off the dust, we each do what we can to help others build a better life here in Maryland. That's our mission, that's our cause and that's our fight."

Mizeur staked out the some of the most controversial positions in the campaign, vowing to legalize marijuana and use the tax revenue to pay for universal pre-K. She also pledged to tax millionaires, cut taxes for 90 percent of state residents, hike the minimum wage to $16.70 an hour and prohibit fracking. Her low-budget bid attracted a small but passionate following among progressive activists.