BOSTON (SHNS) – One week after polls closed, voters still do not know the winners in two Massachusetts House races that are likely headed toward recounts with high stakes for the already-depleted Republican minority.

Election officials in Pepperell, Dunstable and Groton plan to meet this week to count additional late-arriving ballots in the race for their open state representative seat, where Republican Andrew Shepherd leads by fewer than a dozen votes over Democrat Margaret Scarsdale.

Further to the east, a trickle of eligible votes counted after the initial Election Day burst has slashed Georgetown Rep. Leonard Mirra’s tight margin to a nearly microscopic one. It wasn’t clear Tuesday whether any more ballots are still outstanding, but a recount appears likely to decide whether the incumbent Republican secures a sixth term or first-time Democratic challenger Kristin Kassner flips the seat.

On Election Night, Mirra tweeted that he led by 83 votes with all precincts reporting and is “excited to get back to work” on Beacon Hill.

Based on a News Service analysis of publicly available results on Tuesday, with more than 24,000 votes cast, Mirra’s lead now appears to have shrunk as low as single digits.

“We’re closing the gap if we have not already closed the gap,” Kassner, who did not say definitively if she would seek a recount, told the News Service on Tuesday afternoon.

Mirra found himself trying to secure the votes of a largely new constituency under the new political map lawmakers approved. The current North Shore district he represents covers Georgetown, Groveland, Merrimac, Newbury, West Newbury, and parts of Haverhill and Boxford; the updated version for the next decade tilts further southward across Georgetown, Hamilton, Ipswich, Newbury, Rowley and part of Topsfield.

Recounts, where elections workers tally ballots by hand in public, can only take place in Massachusetts contests if a candidate requests one by securing sufficient voter signatures on a petition. To secure a district-wide recount, the margin must be within one half of one percentage point of the votes cast — a requirement that both the First Middlesex and Second Essex races would meet — while no such margin limit exists for recounts of individual precincts.

Candidates must submit district-wide recount petitions with Secretary of State William Galvin’s office by 5 p.m. Friday.

In the race for the First Middlesex District that covers Ashby, Dunstable, Pepperell, Townsend and parts of both Groton and Lunenburg, a News Service analysis of unofficial results on Tuesday found Shepherd in the lead by 11 votes among more than 20,000 cast.

Pepperell election officials will meet Wednesday at 9 a.m. to tabulate additional mail-in ballots, Dunstable will follow suit on Thursday at 1 p.m., and Groton will do the same Friday at 10 a.m.

The pool of outstanding votes could be more than enough to tip the contest in either direction. Zack Gavel, Scarsdale’s campaign manager, estimated the trio of communities collectively has another 25 to 50 votes to add.

“In a race that has this narrow of a margin, if there’s even a couple of those outstanding, that could be significant,” Gavel said.

Even once the final ballots are added to the totals, that might not completely close the book on the contest. Both candidates have picked up petitions to seek a districtwide recount.

Shepherd told the News Service it’s “too early to tell” but “likely” the election will come down to a recount.

“The race is still very much undecided,” Shepherd said. “We’ve had a number of towns already count some mail-in ballots. To our knowledge, we’re still up, but we’ve got towns counting tomorrow and Thursday as well as some overseas ballots that could be coming in and provisional ballots.”

Asked if Scarsdale would seek a recount once the numbers are finalized, her campaign manager said they are “keeping all of our options open.”

Last week marked the first general election in Massachusetts with a permanent law in place allowing widespread voting by mail and expanded early voting after both options proved popular and successful on a temporary basis earlier in the COVID-19 pandemic.

Under the law, any ballot postmarked inside the United States by Election Day counts as long as a local election official received it by 5 p.m. on Saturday, Nov. 12. Ballots for overseas voters can arrive up until 5 p.m. on Friday, Nov. 18 and remain valid.

Gavel said the campaigns are unlikely to have a “quick answer” for voters who want to know the winner in the race, given the ongoing wait for overseas ballots and the time that would go into a potential recount, but stressed that constituents should “continue trusting that the process is working as it’s intended to play out.”

“It could be a matter of weeks instead of days before we have a final answer,” he said.

Shepherd, who interned on Beacon Hill during college and today owns Bayberry Hill Water Company, is vying to keep the somewhat reshaped district represented by a Republican and stave off further erosion of the House GOP caucus.

Most of the communities in the new First Middlesex District were represented for more than a decade by former GOP Rep. Sheila Harrington of Groton, who resigned in February after Gov. Charlie Baker tapped her to become clerk magistrate of Gardner District Court.

The latest decennial redistricting altered the district that Harrington held, splicing out some Groton and Ayer precincts and adding parts of Lunenburg.

If she emerges victorious, Scarsdale, who previously chaired the Pepperell Select Board, would flip the district.

Democrats are already poised to increase their veto-proof House supermajority to at least 132 of 160 seats, three more than where they began the 2021-2022 lawmaking session.

A win for either Kassner or Scarsdale — or both — would add to the gains that already surpassed insider expectations in a bruising cycle for Massachusetts Republicans, who in addition to shedding in the House lost all statewide races in a clean sweep.

Mirra is also hoping to avoid becoming the only incumbent representative or senator to lose a reelection bid in Tuesday’s general election. A single lawmaker, Rep. Marcos Devers of Lawrence, lost to a primary challenger in September.