If you’ve been following Delta’s SiteSeer site, then you know about the SiteSeer Challenge, an online travel contest that features five teams competing to win one million Delta SkyMiles and 400,000 Hilton HHonors points. To drive traffic to the site, Delta is offering bonus miles to visitors who vote in the competition. There are four rounds of voting and you can still earn 250 bonus miles for voting Sept. 3-5 and in the final elimination round Sept. 17-19. The total miles you can earn during the competition is 2,000.

After you’ve checked out the travel videos of the teams visiting each destination (first stop, Budapest), you can vote for the video that most makes you want to visit. You can also check out the teams’ blogs and post in the forums.

American Express cardmembers can earn double flown miles as part of the SiteSeer Challenge. Register on the site before Sept. 19, 2007, and then use any American Express card to purchase a ticket on delta.com for a flight that is completed by Sept. 30, 2007 and you’ll earn double miles on all flights.

Delta launched the SiteSeer site in June, which features short downloadable travel videos of global travel destinations. Delta employees, primarily flight attendants, are your virtual travel guides and they provide inside information, travel tips and hidden secrets when visiting cities such as Boston, Prague, New York City and Mumbai. Visit http://insideflyerus.wpengine.com/link/?546 to vote for your favorite team and get your bonus miles.

Editors’ Note: See our 60 Seconds interview with one of the contestants vying for the one million Delta miles and 400,000 Hilton points.