TAMPA -- When Peter Henderson arrived at his polling place today, he thought his troubles were over.

The 18-year-old had already run into snags when he tried to register to vote -- his form was sent back to him because he included his whole Social Security number instead of the last four digits -- but he was excited to cast a ballot for the first time.

Because he didn't get his form back in time to re-send it before the deadline, Henderson never got a registration form. He didn't know which precinct to go to. "I was running around all day," he said.

He finally went to the Supervisor of Elections Office, where representatives told him he was, in fact, registered, and his precinct was 867. He went to his polling place, the Countryside Baptist Church on Sydney Road.

But Henderson was turned away because he was wearing an Obama T-shirt. "I had to go outside and take it off, and then they let me vote," he said. Election rules do not bar wearing apparel supporting a candidate at the polls.

And on top of that, he had to cast a provisional ballot because poll workers said the issue of his Social Security number had not been resolved.

"It really amazed me," Henderson said. "It'll make me be aware of what may come next time around."

Kim Wilmath, Times staff writer