Like the other colonial regions, the government of the Southern Colonies was democratic to the extent of voting and participation in decision-making. Voting and election to the legislature were limited to white male property owners. To be considered for a legislative position you would have to have an annual income and paid taxes. You were also required to be a member of the Christian church. The leaders of the governing bodies were chosen, but ultimately they had to meet the criteria set forth by the Proprietary or Royal Government.
Proprietary means the monarchy had granted land to the people colonizing. Royal refers to rule directly by the Monarchy. So though the colonies elected the legislature and governor the King of England had an influence on both the candidates for office and later how they governed. The Governor was considered an extension of the monarchy and frequently consulted with the king or representatives of the king.
The legislature was organized similar to the British parliamentary system. In the early stage of colonial governance, there were two houses known as the Upper House and Lower House. The Upper House was appointed by the Governor, and the Lower House was elected delegates by voters. Any laws passed could be vetoed by the Governor, and the King could change the law any time within three years after it was passed. The colonies were an extension of the English government, and the notion of self-rule was limited to settling mundane matters of managing the daily colonial affairs. For example, the court system followed the same procedures and ruled on issues of law as if they were holding court in England. All of the English colonies had this in common.
Though the Southern colonies were democratic in form as were all the colonies, in the function the King of England maintained the ultimate decision-making authority. It is fair to say the governments over time adapted to the pragmatic need for local authority and became more liberal in form and function. So while the Southern colonies maintained a similar structure to the English style of parliamentary government, they did tweak the role to fit the needs of the colonies as they became more self-sufficient and less dependent on the English monarchy to make decisions.