Natalie Dylan, 22, claims her offer of a one-night stand has persuaded 10,000 men to bid for sex with her.
Last September, when her auction came to light, she had received bids up to £162,000 ($243,000) but since then interest in her has rocketed.
The student who has a degree in Women's Studies insisted she was not demeaning herself.
Miss Dylan, from San Diego, California, USA, said she was persuaded to offer herself to the highest bidder after her sister Avia, 23, paid for her own degree after working as a prostitute for three weeks.
She said she had had a lot of attention from a wide range of men, including "weirdos", "those who get really graphically sexual about what they want to do to me" and "lots of polite requests from rich businessmen".
Miss Dylan said she did not think it was particularly significant to be willing to sell your virginity and insisted that she was happy to undergo medical tests for any doubters.
She said: "I get some men who are obviously looking for a girlfriend but I try and make it clear that this is a one-night-only offer.
"I know that a lot of people will condemn me for this because it's so taboo but I really don't have a problem with that.
"My study is completely authentic in that I truly am auctioning my virginity but I am not being sold into this. I'm not being taken advantage of in any way.
"I think me and the person I do it with will both profit greatly from the deal."
She added: "It's shocking that men will pay so much for someone's virginity, which isn't even prized so highly anymore."