Waiting in line poll

I put up a poll about an hour ago asking:

"How long would you be willing to wait in line to vote?"

The results are as follows:

21 - Less than 30 minutes
11 - 30 minutes to 1 hour
10 - 1 hour to 2 hours
4 - 2 hours to 3 hours
19 - More than 3 hours

I understand those that aren't willing to wait long at all; I also understand why people would chose to wait a very long time (the reasoning, not the reason). But is the one to two hour time frame significant? Is that the level of opportunity cost that hits a wide swath of the public? Apart from those that take a strict rational voting stance (assumed to be the low end), and those that take a strict civic duty stance (the high end), do the middle provide a decent estimate of the value of voting?

Edited: I'll adjust the number accordingly throughout the day...