The president himself campaigned for Deeds in Virginia last week. Some of his aides, however, privately signaled last month that they thought Deeds -- hardly an impressive campaigner -- was likely to lose.
Deeds conceded defeat shortly after 9 pm ET: "We've got a whole pile of work ahead of us, and just because we didn't get the right result tonight, doesn't mean we get to go home and whine," said Deeds. "We've got to keep working, and keep fighting. And I'm fighting!"
Democrats point out that the party in the White House has lost the governor's mansion in Richmond in every election since 1973.
But the race is a setback to Democrats' hopes to realign the electoral map in a big Southern state. And it questions whether it's possible for Democrats to motivate independents and those who haven't voted frequently in the past without a candidate named "Obama" on the ballot.
ABC News' Steven Portnoy, Aaron Katersky, and David Chalian contributed to this report.