The West Bank Palestinians have never voted for Hamas because they can't because the Palestinian Authority has taken control and won't allow elections for their people. But if there was a vote, if they were able to vote then they would support Hamas or any Islamist extreme group against Isreal.
The same with Gaza, there have been no elections since Hamas got in. They don't allow the people freedoms ot democracy. They shut down any talk against them and as we have seen are willing to kill their own people to push their ideology.
So the real issue at stake here is not the land but who will create a free and peaceful place for people to exist regardless of belief, race or ethnics. I don't think Hamas, the PA or any radical Islamist group is capable of creating a safe and free nation let along share the space within another nation trying to establish what the rest of the West and what Isreal has had.
Until they either learn to allow people to be free, to 'believe in other beliefs', to vote for whoever, to live equally regardless of ethnics, gender and sex then they are a threat not just to Isreal but to the free West. If Isreal goes then next it will be New York, London, Toronto and Sydney which is already beginning to happen.
I would say the avergae Palestinian if allowed to get away from the brainwashing of groups like Haamas then they would be able to establish themselves as a people and probably live in relative peace with Isreal. Though unfortunately in some ways its the nature of their belief that allows radicalization.