The Biggest Threat To The United States Is A President Who Won With Over 50% Of The Vote?

I've said that I'm not voting for Obama or Romney. I'll be looking at third party options. This chart, however, angers and frustrates.  Dan Amira polled 50 random delegates to the Republican convention. One of the questions was "What is the greatest threat facing the United States?" According to a majority of the Republican delegates Amira polled, the greatest threat is a President elected with the majority of the vote:

Amira points out that some of the delegates objected to his foreign policy choices:

Mea culpa: This question did not include economic threats as choices. So if a delegate protested that the options available weren't sufficient, they were invited to write in their own. Here's what they wrote:

Economic collapse
Fiscal and moral decline
Natl debt and growing federal govt
Current moral decline
Debt
Economic collapse

I know the sample is small, but I'm not unsure that the results are inaccurate. Further, I really don't know if it's possible to have a civil political discussion or campaign if one views one's political opponent as an existential threat to the nation. Diplomacy has been called war by other means; apparently some Republican delegates believe that politics is also a form of warfare.

HT: Andrew Sullivan