First of all, Bernie, the places which have paper ballots are the ones with tiny numbers of constituents. It's easier to count 12 people than 1200.
Secondly, Diebold (it rhymes with "feebled") got into this game by being a security devices company. Diebold safes have been an industry standard in banks since the Civil War. They are the first makers of ATM machines. They do security at banking levels, where actual cash dollars are at stake, and their polling machines are no more likely to be hackable than their ATMs. Yes, they can probably be hacked on an individual basis, but we're talking hundreds of individual machines.
It's easier to stuff a paper ballot box than an electronic one, anyway.
Third, these are meaningless primaries in states which have no influence whatsoever on the outcome of the nominations. It's a media circus, and nothing more. No one would go to the trouble and expense of hacking the machines for what is basically zero return on their investment.
Finally, people lie. Pollsters are not putting people under oath or sucking the information from them under sodium pentathol trance, waterboarding or Vulcan Mind Meld. It's a secret ballot, Bernie. What people say in public ("sure I'd vote for a black guy") ain't necessarily what they will actually do in the voting booth ("no way am I voting for one of those coloreds, I'm picking Clinton - she's twice the man Edwards is").
Edit Add: I just tried to find the broadcast on KGO's archives - they have a setup where you can play each hour's audio from the current week online, just tell them the day and the hour - and I cannot find the voice or the words I heard. The KGO site is clear that Brian Copeland was on the air when I was listening. If anyone wants to try to find it for me, the archive site is here:http://www.kgoam810.com/Article.asp?PT=Archive&id=49920