The election was rescheduled for Wednesday from 7 a.m. to 10 p.m.
The vote for Homecoming king and queen was unaffected, and the results will be announced Saturday at the home football game against the University of Maryland.
Senior Class President Paymon Rouhanifard said some seniors who tried to vote through Student Central were classified as juniors and were unable to vote for the class gift.
He said that almost 40 seniors e-mailed him throughout the day and that many others stopped by the senior class office to let them know about the problem.
Rouhanifard did not know the exact number of seniors who could not vote for the gift. "We don't know how many votes we lost," he said.
Board of Elections Chairman Brian Fauver said the problem was that the class standings used for the vote were from February. He said only students who held senior standing for the spring 2002 semester were able to vote Wednesday.
Rouhanifard sent an e-mail to the senior class Wednesday morning, writing that the problem was occurring for people trying to vote at off-campus locations.
But student government later discovered that some seniors could not vote on campus either.
Rouhanifard encourages all seniors to vote next week and said he is happy that everyone should get to cast a ballot.