Maryland is increasingly a city-state - all of its districts are partially in either metropolitan Washington, D.C. or Baltimore. The state has long been a Democratic stronghold. Initially, a Democratic machine in Baltimore combined with voters on the culturally southern Eastern Shore to form a Democratic majority. In the 1960s and 70s, however, the Democrats began to lose the Eastern Shore, but offset the losses with gains in the suburban DC counties of Prince George's County and Montgomery County. Post Civil War, the state has elected only six Republican governors, and only one has managed a second term.
The last Republican governor, Bob Ehrlich, won an open seat in 2002 against Kathleen Kennedy Townsend, a disappointing candidate for Democrats. Ehrlich had a tempestuous relationship with the Democratic legislature, and in 2006 he was defeated by Baltimore Mayor Martin O'Malley.
O'Malley's approval ratings declined after imposition of a tax hike and other measures designed to balance the state's budget. Ehrlich announced his intention to seek a rematch earlier this year. Both men are below 50 percent in the polls, and since both are incumbents of sorts, the usual "incumbent rule" may not apply. The RCP Average has O'Malley ahead by .5 points.
Sean Trende is Senior Elections Analyst for RealClearPolitics. He can be reached at strende@realclearpolitics.com.