Dowdy ran unopposed to succeed Rickey Cole, who had led the party since August 2001.
Mississippi Democrats once dominated statewide politics, but they've seen that power slip.
Last November, former Republican National Committee chairman Haley Barbour defeated Democratic incumbent Ronnie Musgrove for governor.
Political newcomer Tate Reeves, a Republican, beat former state fiscal officer Gary Anderson for treasurer.
In late 2002, Lt. Gov. Amy Tuck walked away from the Democratic Party to become a Republican.
Dowdy, who served in Congress from 1981 through 1989, is a folksy, plainspoken lawyer who can be both tough and funny.
Those are two of the reasons why House Education Committee Chairman Randy "Bubba'' Pierce said he believes Dowdy is the right man for the job.
Pierce said Dowdy will do a good job articulating what the Democratic Party stands for.