Istanbul, Turkey - Turkish citizens will vote on Sunday in a referendum that might deeply change how Turkey is governed by significantly expanding the powers of the country's presidential office.

The proposed constitutional changes are backed by Turkish President Recep Tayyip Erdogan, the ruling Justice and Development Party (AK Party) he founded and the far-right Nationalist Action Party (MHP).

They are opposed by the centre-left Republican People’s Party (CHP) and the pro-Kurdish People's Democracy Party (HDP).

Both "Yes" and "No" campaigns claim that they lead the polls and are closer to victory.

For months now, they have been working to convince voters to side with them in upcoming key vote.

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