Today's vote replaces a fraud-riddled parliamentary election in November. That ballot sparked protests against then-President Eduard Shevardnadze that eventually led to Saakashvili's election in January.
Reports say the vote will test the political strength of Adjar leader Aslan Abishidze. Saakashvili has demanded that Abishidze submit to the will of the central government -- something the Adjar leader has been reluctant to do.
Saakashvili has sent Prime Minister Zurab Zhvania to Adjaria to encourage voters to support the central government.
First results are expected early tomorrow.