Voting in an election is permissible [mubah] by default. It is neither an obligation nor is it prohibited. If you vote, you should have the intention to improve society for the better, or minimize harm, in accordance with what Allah wants. It does not matter whether the candidate is Muslim or not. Whoever is more likely to bring about greater good, from the Islamic definition of what is ‘good’, should be preferred.
Shaykh Mustafa Umar