As polls closed Tuesday, Republican David Jolly had overtaken Alex Sink's initial lead, setting up a cliff-hanger.
By 7:20 p.m. Jolly was leading with 48 percent of the vote to Sink's 47 percent. But the race is expected to be close, with scores of voters casting ballots in person Tuesday.
The Pinellas County Supervisor of Elections estimated voter turnout at 39 percent through 6 p.m. That includes the unofficial early voting turnout of 27.6 percent and 11.4 percent turnout at the polls.
The race between Jolly and Sink has garnered national attention and prompted contributions of an unprecedented $12 million in campaign funds.
Poll workers at the Gulfport Presbyterian Church reported a "steady stream" of voters
St. Petersburg College professor Scott Copper voted along Democratic Party lines.
"I like them in charge," said Cooper, 50, noting that he likes where Sink stands on issues such as health care.
The barrage of negative ads forced him to not watch television for the last month. Still, he doesn't think the ads sway many voters.
Bernard Wright, a retired pipe fitter from Michigan has called Gulfport home for more than 20 years. The World War II veteran stood in front of the church thanking voters for doing their civic duty.
"I'm glad people voted," said Wright, 86. "I don't care who they vote for, even a Republican."
Wright, a Democrat, said he voted for Sink. He fears the negative ads might turn people off from voting.
"I'm sick of it. I see no reason for it."
He speculates that the ads might sway people who don't follow politics.
"They tend to believe what they see and hear. A lot of people are confused because of the ads and that makes matters worse.
As he continued thanking voters, Wright said: "A lot of people died for this right. It's our inalienable right to vote even if it's for a Republican."
Marilyn Fields, 71, preferred to cast her ballot in a booth instead of through the mail. The Democrat voted for Sink because of her stance on health care.
"I believe in what she stands for. She's a good moderate."
Fields said she received 10 phone calls Monday night about the candidates.
"I think they are aiming for the seniors," she said about the negative ads. "They're wrong. The info is misleading. If you don't investigate it yourself, you won't know."
The national attention on the election doesn't surprise her, she said, adding: "It will forecast the midterm elections."
Jolly's position on health care pushed Dave Falwell, 59, to back his opponent.
"I don't hate the Affordable Care Act," the retiree said. "People should give it a chance to see how wonderful it is."
He also said he didn't think that Jolly would work across party lines, adding: "There needs to be more partisanship in Washington."
While Falwell doesn't watch much television, his mailbox did swell with ads. He believes the ads hurt all candidates. "Once you put out a lie, it grows."
While waving a sign for a municipal candidates at the Gulfport Municipal Library, Eileen Clancy said she voted for Jolly because of his position on health care.
"I don't like defamation of character," she said about ads attacking Jolly. "I've seen more ugly, ugly things with Sink. If you have to do that, you're reaching."
Zlatko Horvatich, 72, said he couldn't get past Jolly's career as a lobbyist in Washington, D.C. and his positions on Social Security and health care.
"That's what turned me off," the retiree said. "I would never vote for a lobbyist for office."
Beverly Dickinson, 65, focused more on the climate than Social Security and health care. Still, the Democrat voted along party lines.
"Anyone who denies the existence of global warming doesn't deserve a place in Congress," she said.
Early-morning voters at Saint Bede's Episcopal Church said they had a clear choice.
George Harasz, 46, sales account executive from St. Petersburg, said he voted for Alex Sink.
"I think we need more Democrats in the Congress,'' he said.
He said he was not moved by all the attack ads and outside money involved in the race.
"It didn't change my mind a bit,'' he said. "I didn't believe any of that. I understand where that special interest money is coming from. You've got to stick to your beliefs when it comes to that,
A registered Republican, Harasz said he is fed up with the gridlock in Congress.
"I'm tired of all the rhetoric,'' he said.
Gary Hicks, 48, an IT professional, voted for Jolly.
"I want better management of our system in general,'' he said.
In terms of attack ads, he said, "David Jolly was attacked. He was misrepresented.''
He thought the ads reflected poorly on Alex Sink.
Laura Vittetoe, 27, an attorney in St. Petersburg, voted for Sink.
"I tend to vote Democrat,'' she said. "I believe the tea party candidate, David Jolly, would be a disaster.''
She said Sink offers a balance of fiscal conservatism with more liberal social policy.
Voters also turned out early at precinct 134, at Sunken Gardens
Jason Spears, 35, is a contractor who said David Jolly's commitment to repealing Obamacare made him the best choice.
"It all came down to healthcare," Spears said. "We're small business owners, and the impact it will have on us and on employees is fairly catastrophic."
In the same polling place, Paul Kurtz, 43 said he voted for Alex Sink because "she's a better representative of where the community is as a whole."
Kurtz, a democrat, said it will be hard to live up to the legacy of C.W. Bill Young, the long-time District 13 representative whose death last fall prompted the special election.
"I definitely appreciate him now," Kurtz said.