Democratic nominee Scott Colom added slightly to his narrow lead over incumbent Sen. Cindy Hyde-Smith in the Mississippi Senate election as two key ballot deadlines hit Tuesday.

Colom, a local district attorney, as of 4:30 p.m. ET, was ahead of Hyde-Smith by 2,607 votes, out of 953,547 votes counted, with an estimated 97% of the votes in, according to the Associated Press. That’s a margin of just .27 percentage points.

Independent candidate Ty Pinkins had 20,034 votes.

Tuesday is the deadline for resolving so-called affidavit or provisional ballots, which are cast by voters whose eligibility is disputed or unclear on Election Day. It is also the deadline for the receipt of mail-in absentee ballots that are postmarked by Election Day, Nov. 3.

Mississippi is one of just two states whose Senate election has not been called. Alaska is the other.

Democrats so far have flipped seven Senate seats held by Republicans going into the election. That gives Democrats a new majority in the Senate of at least 54 seats in the 100-member chamber come January.

Alaska before Election Day was viewed as possibly key to the question of whether Republicans would retain their narrow majority in the Senate.

Mississippi, which has not elected a Democratic senator since the segregationist John Stennis in 1982, was on few political analysts’ radar as a possible pickup for Democrats. If Colom wins his race, he would be the first Black senator from Mississippi since the post-Civil War Reconstruction Era.

In Alaska, Democratic nominee Mary Peltola is ahead by just 2,517 votes over incumbent Republican Sen. Dan Sullivan, with 218,641 total votes counted, a margin of 1.1 percentage points.

Peltola has 48.6% of the total vote. If neither she nor Sullivan gets more than 50% of the total vote, the race will go to a ranked-choice round, in which the two other candidates, Gerald Heikes, and another candidate named Dan Sullivan, will be eliminated, and the second choices of voters who made them their first choice will be allocated between Peltola and the incumbent.

Mississippi’s uncalled Senate election could provide one of the biggest shocks in a midterm election cycle already chock full of stunning defeats of Republican candidates.

Sen. Cindy Hyde-Smith, the GOP incumbent, is trailing Democratic nominee Scott Colom in an extraordinarily tight race in normally solidly red Mississippi.

Colom led by 1,724 votes out of 930,728 votes counted as of Thursday afternoon, according to the Associated Press. Ty Pinkins, an independent candidate, had 19,978 votes, or 2.1% of the total count.

A final result may not be available until next week because more ballots can still arrive and be counted.

Mississippi’s election procedures do not have an automatic recount provision.

“Absolutely, I didn’t think it would be this close,” said Brian Anderson, a political science professor at the Mississippi University for Women in Columbus.

Anderson said that before the election, he thought Colom, a 43-year-old district attorney, might get into position to lose by just 3 or 4 percentage points, which would have been a very solid showing in a state that hasn’t elected a Democrat to the Senate since 1982.

“I’m much more surprised” now that Colom has a chance to win, Anderson said.

If Colom defeats Hyde-Smith, 67, he would be the first Black senator from Mississippi since the post-Civil War Reconstruction Era.

“The Democrats have struggled here to create a pipeline of candidates,” Anderson said. A Colom win “would galvanize the Democratic Party in a way it has not been,” he said.

Neither candidate’s campaign immediately responded to requests for comment from CNBC.

In a pair of ironic twists, if Colom wins, his victory could be attributed in some ways to actions taken by two Republicans: President Donald Trump and Hyde-Smith herself.

Supreme Court Justice Amy Coney Barrett, whom Trump appointed, wrote the court’s 5-4 majority ruling in June that upheld a Mississippi law allowing mail-in absentee ballots postmarked by Election Day to be counted if they are received within five business days.

Those ballots could provide Colom a margin of victory. There are also an estimated 10,000 to 15,000 provisional ballots that require verification of eligibility to vote.

A lawyer for the Republican National Committee, whose lawsuit argued federal law barred counting votes received after Election Day, noted in a brief to the Supreme Court, “Democratic voters tend to mail their ballots later on average than Republican voters, which results in late-arriving ballots favoring Democratic candidates.”

Trump at the time of the Supreme Court ruling called it “a tremendous loss” for voters’ rights.

Hyde-Smith was appointed to her Senate seat in 2018 after the resignation of Thad Cochran and later that year won a special election for the seat. She was elected to a full term in 2020.

In 2023, she effectively blocked Colom’s nomination by then-President Joe Biden to a post as a federal judge for the Northern District of Mississippi. Colom’s nomination had the support of…