BRIDGEWATER, Va. (Reuters) - More than 140 years after the Civil War raged across its tobacco fields, Virginia finds itself in a new north-south conflict pitting its northern suburbs against the rest of the state.

Democrat Jim Webb narrowly defeated incumbent Republican Sen. George Allen in Tuesday's election, thanks to strong support from the Washington, D.C. suburbs of Northern Virginia, tipping control of the U.S. Senate to the Democrats. The region's voters also have sent two successive Democrats to the governor's mansion.

It's a sign that what was once an overwhelmingly conservative state is increasingly dominated by Northern Virginia's racially diverse, densely populated suburbs across the Potomac River from Washington, experts say.

Those in the northern part of the state say their cosmopolitan outlook stands in stark contrast to the rest of Virginia, which was the home of the Confederacy's capital during the Civil War in the 1860s.

CNN's County breakdown of Virginia Senate vote