'Fantastic event'
The finals take place on Thursday, televised on ESPN sports channel, following the semifinals in the afternoon.
For the past five years, the annual National Spelling Bee has been clinched by youngsters of South Asian heritage - a reflection, some say, of the overriding importance their families place on educational excellence.
"I don't think anything in particular makes them so special besides hard work and a culture that is obviously encouraging them," said Jacques Bailly, the 1980 champion who now is the event's chief word pronouncer.
"This is a fantastic event," the University of Vermont classics professor said. "There are no quotas. These (contestants) are winners, and they look to me like a wonderful cross-section of America. It inspires me."
Fifteen contestants were knocked out in Wednesday's first public rounds that began with "glasnost" and "perestroika" - Russian words from the final years of the former Soviet Union when none of the competitors had yet been born.
Learning to be a perfect lady proves fruitful