Complex sentence: Since Sindh was a constituency and not a province, this meant that campaigning needed to be done across the entire province, from the distant Upper Sindh Frontier region to the far reaches of the Thar desert.
Split into simpler sentences: Since Sindh was a constituency and not a province. This meant that campaigning needed to be done across the entire province, from the distant Upper Sindh Frontier region to the far reaches of the Thar desert.