Ben McAdams holds a 1,229-vote lead over Rep. Mia Love after Salt Lake and Utah county election updates

Leah Hogsten | The Salt Lake Tribune Utah's 4th Congressional District Democratic challenger, Salt Lake County Mayor Ben McAdams, is congratulated on a race too close to call at the Utah Democratic election night headquarters at the Radisson Hotel in Salt Lake City, Tuesday, Nov. 6, 2018.

Democrat Ben McAdams held his tenuous lead over Republican Rep. Mia Love on Tuesday after the addition of roughly 40,000 votes to Utah County’s election totals and 17,000 votes in Salt Lake County.

McAdams now leads with 50.3 percent of the vote, compared with 49.7 percent for Love, a margin of 1,229 votes.

Dave Hansen, Love’s campaign manager, expressed optimism after seeing the new Utah County figures.

Ben McAdams' lead over Mia Love in the 4th Congressional District race has narrowed

“The numbers are moving in the right direction," he said, “and we are diligently watching for additional results.”

McAdams is currently winning in Salt Lake County, while trailing Love in the parts of three other counties — Utah, Juab and Sanpete — that make up the 4th Congressional District.

His success in Salt Lake County is critical to maintaining his lead, but McAdams has seen his margin there slip incrementally since the initial results on election night.

“The mayor’s lead continues to hold, and we remain optimistic about the final tally," said Andrew Roberts, McAdams' campaign manager. "We will continue watching results as they come in.”

The wait isn’t expected to end anytime soon. Chief Deputy Utah County Clerk-Auditor Scott Hogensen said no more vote totals will be released by his office until Friday.

“I’m sure there will be more [ballots left to count] after Friday," Hogensen said. “We’ll be done with the bulk of it by Friday."

Salt Lake County intends to continue doing daily vote counts and disclosures.

Maine election officials, including Democratic Deputy Secretary of State Julie Flynn, right, began counting ballots on Friday, Nov. 9, 2018, in Augusta for the Second Congressional District's House election. The election is the first congressional race in American history to be decided by the ranked-choice voting method that allows second choices. (AP Photo/Marina Villeneuve)

Nate Silver, a political handicapper and founder of the website FiveThirtyEight, tweeted early Thursday that the race still appears to favor McAdams. But Silver clarified later that the prospect of a Democratic win in the district had slipped from “likely” to a “lean.”

Despite the race not being finalized, McAdams was expected to be in Washington on Tuesday afternoon to participate in orientation meetings for new members of Congress. He was one of 10 freshmen — one Republican and nine Democrats — who are leading in currently undecided races.

In Utah, for a race to go to a recount, the margin would have to fall within 0.25 percent.

Leah Hogsten | The Salt Lake Tribune Salt Lake County elections officials tabulate votes from ballots, Tuesday, Nov. 13, 2018, at the Salt Lake County building.