[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2010/images/04/27/art.martin.gi.jpg caption="Gov. Martin O'Malley of Maryland began his re-election bid Tuesday."](CNN) – Maryland Gov. Martin O'Malley Tuesday officially kicked off his bid for re-election. His challenger is former Republican Gov. Robert Ehrlich, the man he knocked out of office four years ago.
O'Malley, a Democrat, began his three-day swing across the state with an event in Baltimore, where he served as mayor for two-terms before beating Ehrlich in the 2006 gubernatorial contest.
In his speech, which according to a prepared text focused on job creation and on the tough economy facing the state, O'Malley said "because of the tough decisions made, Maryland has fared better than most, but we still have more work ahead of us."
In what appears to be an attack on Ehrlich, O'Malley added that "others may want to take Maryland back." Instead, he promised to "move Maryland forward."
Earlier this month, Ehrlich kicked off his bid for his old office.
"Welcome to history, part two," he told a crowd in Rockville, Maryland, which is located in the heavily Democratic Montgomery County. Ehrlich also held a rally in Baltimore County, the area he represented in Congress for eight years. In 2002, then-Rep. Ehrlich upset Democratic Lt. Gov. Kathleen Kennedy Townsend to become Maryland's first Republican governor in over 30 years.
While it's an extremely tough political climate for any incumbent seeking re-election, the state is dominated by Democrats. Charlie Cook and Stuart Rothenberg, two well respected non-partisan political handicappers, both rate the race as competitive but give the advantage to O'Malley.
Follow Paul Steinhauser on Twitter: @psteinhausercnn