In local elections where only a few dozen people vote for certain positions, intimidation is a genuine possibility. But more than that, transparency can cause people to vote differently. For example, after an election the voters always poll as having voted for the winner at a higher rate than they actually did, indicating that a lot of people vote differently than they would prefer the public know.
---------- Post added 2012-09-01 at 11:38 PM ----------
1. If who you vote for is private, the coercion is a moot point.
2. Whether they know or not doesn't matter, because none of this matters.