On March 6, Ron Paul carried one U.S. House district in Virginia, the 3rd district. That district is Virginia’s only black majority district. It includes parts of Norfolk and parts of Richmond, and a narrow string of territory linking those two cities.
Here is an article about the low turnout in that primary. Only slightly more than 5% of Virginia’s registered voters voted in the Republican presidential primary. There was no Democratic presidential primary. Virginia has open primaries, so any registered voter was free to vote in the Republican presidential primary.
Because Paul carried the 3rd district, he picked up three delegates.