Stump the Person Below You! (Game)

[Quantum Leap]

Ten men are about to be executed. They don't like the idea, but they are willing to sacrifice themselves so that others may live. The execution is explained to them. They will be lined up single file, facing the same direction. Each man will be looking at the back of the person in front of him, except for the man in the front of the line. He has noone's back to look at. Each of them will be given a black or white hat on their head. Starting at the back of the line (the man who can see everyone else) they will ask him to state his hat color. If he guesses right, he will be allowed to live. This process continues up the line until each man has been executed or released. The execution is scheduled tomorrow morning. Tonight they must come up with a strategy. How many men can they guarantee will live, and what strategy will ensure this?

There are NOT necessarily five black and five white hats.

Addendum for all of those thinking the first guy can just shout out the hat order and sacrifice himself:
If the men say any word other than "black" or "white," then they are all executed. If the men speak a word at any time other than when they are asked for their own hat color, then all will be executed. If the men say more than that single word in response to the question, then all are executed.

You didn't say anything about their voice pitch when they answer the question, right? Assuming the executioners are only concerned about what they're going to say (one word/answer, either black or white), and all of the men have no hearing/seeing disabilities ... they can use this strategy:

Last person [in the line] will have to risk it and sacrifice himself. Whatever his guess (black/white), he should say it in a loud voice if the hat on top of the person's head in front of him is black, and in his normal voice pitch if it's white. The other eight men are to follow this pattern. The last man (the one with no one else in front of him) can say his answer in any voice. lol

Nine (9) people are 100% guaranteed to live. (If the first person got his guess right, then so much the better ... that's 10 out of 10! )

... that's my try. lol