Here's the alternative method to enter the contest without making a donation, you had to search hard for it though:
http://www.barackobama.com/obama-clooney-you/rules
Hmmmm...just noticed something...
Free Entry RulesI won't bother copy-pasting the rules here. What I will say is this.
I see NOWHERE where a person is prohibited from entering more than once...
(IN FACT, once entered, they encourage you to ENTER AGAIN!)...
Ergo, legal inference...
A person may enter as MANY TIMES as he WANTS!...
With no captcha in place... and a special email created especially for this campaign...
(and of course a phone number that I use only for spam purposes as well through google voice)...
Ergo... using iMacros or other automate form entry serive....
...and of COURSE a throwaway email or one in which you could care less about spam...
One could...COULD!... enter a few thousand...or more.... times and kinda up the odds....
NOW...multiply this by a few dozen cavers.... and a few thousand freepers....
(We are not DUmmies...we should get the drift by now!!)
Wink wink...
EDIT: Do you REALLY THINK they are smart enough to use software to limit only one entry? nahh.....