There are 450~ million Arabs and you chose to focus on the 4.5 million Palestinians who voted in elections in 2006. These elections bought Hamas to power in in Gaza and PLO in the West Bank. Gaza is autonomous in terms of governance and has chosen to not hold elections since the last one in 2006. Neither has the PLO. They both plead unable to hold elections because they want to hang on to power though the international community wants them to.
Edit: Getting down voted for stating facts.