Montgomery heads to a recount in the county exec race. Here’s what that means.

Canvassers for the Montgomery County Board of Elections review mail-in ballots for the primary election on July 21 in Germantown, Md. (Bonnie Jo Mount/The Washington Post)

After nearly three weeks of tabulating ballots from the July 19 primary, Montgomery County officials are bracing for another round of counting.

With incumbent County Executive Marc Elrich ahead of Potomac businessman David Blair by only 42 votes, election officials will likely be back to work recounting ballots in this tight Democratic primary.

Elrich declared victory Saturday evening after the final bulk of ballots had him leading by 42 votes — but Blair announced the next day that he planned to petition for a recount.

Many saw this year’s primary as a rematch between Elrich and Blair, who also faced off in the 2018 primary, which Elrich won also by a narrow margin, 77 votes, and also after a recount.

The stakes are high, as the Democratic primary often determines the victor in November in this blue county.

Here’s what you need to know about where the election stands and what to expect as officials prepare for a recount.

2022 Maryland primary elections results