Boards of elections across Maryland will begin counting hundreds of thousands of mail-in ballots Thursday morning. The Democratic nomination for governor and several local primary races hang in the balance.

The mail-in count will determine who won contentious Democratic primary races for State’s Attorney in Baltimore city and Baltimore County.

Other local Democratic primaries still up for grabs include two Baltimore County Council seats and the contest for Baltimore City Sheriff.

In the county state’s attorney’s race, Robbie Leonard has a lead of more than 800 votes over incumbent Scott Shellenberger with all early voting and election day votes counted. As of Wednesday morning, the county had received 31,683 Democratic mail-in ballots.

Leonard said during the campaign they contacted voters about mailing in their ballots through phone calls, door knocking and text messages.

“We reached out every way possible to get people to return their ballots and make the right vote on their ballots,” Leonard said. “We’ll just have to see what kind of response we get.”

In the city state’s attorney’s race, incumbent Marilyn Mosby trails Ivan Bates by more than 4,000 votes in the Democratic primary.

But there were 20,531 more Democratic mail-in ballots received by Baltimore city which could sway the early results.

Baltimore City Sheriff John Anderson trails his opponent Sam Cogen by fewer than 200 votes.

There are two open seats on the Baltimore County Council. In both cases, the Democratic primary is too close to call.

In the county's first district, which includes Catonsville and Arbutus, Delegate Pat Young has about a 700 vote lead over businessman Paul Dongarra.

“I think we still have a race going on,” said Dongarra.

He said 3,600 Democratic mail-in ballots from the first district have been returned to the board of elections.

Dongarra said Young got a big push at polling places and early voting centers from Baltimore County Executive Johnny Olszewski and other Democratic leaders who supported him. The mail-in voters missed all of that so Dongarra is hopeful he will do well with them.

“The 3,600 people that are returning their ballots, they did not have to go through that experience,” Dongarra said.

Young disputes Dongarra’s assessment of how he currently has a lead.

“I believe that the reason we’re ahead is because of the year plus ground game we put together,” Young said.

He said several months ago, his campaign began targeting people who were requesting mail-in ballots.

“The requests were so high, it was a game changer,” said Young.

In the sixth district, which includes Towson, Shafiyq Hinton holds a razor-thin 15 vote lead over Mike Ertel.

Baltimore County Elections Director Ruie LaVoie said once the mail-in count begins Thursday it will be updated daily.

LaVoie said, “Every night of the canvas I will upload the results for that day and add them to the total, the unofficial results.”

LaVoie’s goal is to certify the county’s election on July 29.