The nail-biter playing out in Ohio’s 12th Congressional District got even closer Wednesday after 588 uncounted votes were found in a suburb of Columbus, according to county officials.

The ballots were tallied and Democrat Danny O’Connor gained 190 votes on Republican Troy Balderson. The GOP candidate, who was endorsed by President Trump, currently leads by 1,564 votes.

The Franklin County Board of Elections said in a news release that the newly discovered ballots had not been “processed into the tabulation system,” and the issue was corrected.

O’Connor, who is from Franklin County, celebrated the news by tweeting red sirens and informing his followers that he is confident he will soon be declared the winner. He asked for donations to continue to fight that the votes are “counted fairly.”

The Cincinnati Enquirer reported that 3,435 provisional ballots and 5,048 absentee ballots will be counted Aug. 18, ahead of an Aug. 24 deadline. Ohio requires a recount if a candidate wins by less than half a percentage point.

The winner takes the U.S. House seat previously held by Republican Pat Tiberi, who resigned in January.

The early results were considered a major win by Republicans who insist November’s “blue wave” will turn out to be a ripple.

Democrats, who appeared to come up just shy in another special election, considered O’Connor’s turnout a victory in itself. They point to the fact Trump won the district by 11 percentage points in 2016. The district has had a Republican representative for the last three decades.

"It's one more piece of evidence amidst a lot of others that this is a good environment for Democrats, and it provides some opportunities to the party in the fall," Kyle Kondik, managing editor of Sabato's Crystal Ball at the University of Virginia Center for Politics, told the Cleveland Plain Dealer.

Trump claimed credit for his late push to give Balderson the slight edge, but Gov. John Kasich also backed the candidate who is running for his old seat.

Balderson, a state senator, and O’Connor, the Franklin County recorder, want to complete the term of a Republican who retired in January. The race tests voter sentiment before the general election in November, when Balderson and O’Connor will battle again for the full two-year term.

Balderson celebrated his victory late Tuesday night and told supporters that he’s ready to get to work in Congress. He says, “America is on the right path and we’re going to keep it going that way.”

The Associated Press contributed to this report.