After pulling ahead in the vote count over the weekend, Utah GOP Congresswoman Mia Love, one of the few women of color in the Republican House caucus, has now fallen behind her Democratic opponent, Salt Lake County Mayor Ben McAdams, in one of the few midterm races yet to be decided.
Vote counting was scheduled to be finished Tuesday evening.
After provisional ballots in Democratic-leaning Salt Lake County were counted Monday night, McAdams opened up a 739-vote lead over Love, who has yet to concede the race.
In a press conference Monday evening, McAdams declared victory, calling his lead "insurmountable" and writing on Twitter that it is "Time to put election year politics aside, come together to get things done in Congress for Utah families."
Love issued a written statement Monday evening that did not include a concession.
"I would like to express my sincere appreciation to the voters, who along with our family, have been waiting for two weeks to get election results. Thank you for your continued participation in this process," Love wrote.
(MORE FROM 538: Who Could Become Speaker Of The House If Pelosi Doesn’t?)If McAdams ultimately emerges victorious, his win would increase Democrats' net gain in the House in 2018 to a total of 38 seats, the largest shift in the party's favor since the 1974 election, held in the wake of the Watergate scandal that led to the resignation of Republican President Richard Nixon.
McAdams was also one of 16 Democrats who signed a letter released Monday saying they will oppose Nancy Pelosi's bid to become the next House speaker, lending even greater importance to the race' final result.
Love, the sole African-American woman in the GOP ranks in Congress, is no stranger to close races. She lost her first bid for Congress in 2012 by just 768 votes to Democratic incumbent Jim Matheson, only to win the seat by just over 7,000 votes in 2014.
A Love loss, coupled with the retirement of longtime Miami-area GOP Rep. Ileana Ros-Lehtinen, would further thin the Republican Party's diversity in Congress, and would make Washington Congresswoman Jaime Herrera-Butler the only Republican woman of color in the U.S. House when the 116th Congress is sworn in next year, according to the Center for American Women and Politics at Rutgers University.
In an interview last week with on CBS, incoming House Minority Leader Kevin McCarthy acknowledged that the party could do a better job at honing diversity within its congressional ranks.
"We have room for improvement. If you look at, in the Democratic primaries where there was an open seat and it was a woman versus a man, a woman won 69 percent of the time. So, of course, they had more women coming forward. We can do better in recruitment, and that's what I'm excited about doing."
According to data compiled by ABC News, a total of 114 women were elected to the U.S Congress in 2018. Of those 114, 99 are Democrats and 15 are Republicans.
Another thing Love is accustomed to is criticism from President Donald Trump, who personally lambasted the congresswoman, along with several other unsuccessful GOP candidates this cycle who he claims lost in large part due to their unwillingness to embrace him and his agenda.
"Mia Love gave me no love," Trump said at a press conference at the White House the day after the election, "And she lost. Too bad. Sorry about that, Mia."
(MORE: The sisterhood of congressional 'firsts': Diverse group of newly elected women bond)Love has also been unafraid to criticize President Trump and his administration on multiple occasions, most recently his proposal to end birthright citizenship for children whose parents immigrated to the United States.
"I have always opposed presidential attempts to change immigration law unilaterally," Love said in a statement last month, according to the Salt Lake Tribune, "“The Constitution gives Congress, not the president, the power to ‘establish a uniform rule of naturalization’ and the 14th Amendment makes the conditions of citizenship clear: Individuals born in this country are citizens."
Both Salt Lake and Utah County will complete their canvass of votes on Tuesday afternoon, local officials confirmed to ABC News.