(CNN)Turkey voted Sunday on a referendum designed to hand the country's President Recep Tayyip Erdogan sweeping powers.
Voters were asked to endorse a reform package that would replace the current system of parliamentary democracy with a powerful executive presidency.
Official results have not yet been released, and the opposition promised to contest at least a third of the votes cast. But unofficial results from a state-run agency show Erdogan winning by a small margin, with 99.8% of the ballots counted.
Here's what stands to change in Turkey if the "yes" vote on the referendum becomes official.