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Turks began voting Sunday on a constitutional referendum that, if approved, would fundamentally restructure the country's parliamentary system, giving broad new powers to President Recep Tayyip Erdogan and ensuring Erdogan stays in office for at least another decade.

Under the new proposal, the president would be able to dissolve the legislature, rule by executive order, and gain new authority over administrative and judicial appointments. Here's a breakdown from Al Jazeera explaining further changes:

Polling suggests a slight public preference for approving the new system, and unofficial results will be published by Sunday evening local time.