KEY POINTS:
WASHINGTON - Barack Obama decisively won two more Democratic nominating contests today, extending his winning streak over rival Hillary Clinton and building momentum in a hard-fought US presidential race.
Obama swept to easy victories in Virginia and the District of Columbia, US media projected, running his hot streak
to seven after five consecutive wins over the weekend and expanding his lead in pledged delegates who select the party's nominee.
Republican front-runner John McCain was running slightly behind his last major challenger, former Arkansas Gov. Mike Huckabee, in early Virginia returns as McCain tried to move closer to clinching the party's nomination for the November election.
Maryland officials extended voting, which was supposed to end at 8 p.m. EST, to 9:30 p.m. EST because rain and freezing temperatures created travel hazards throughout the region.
Obama, who would be the first black US president, was favored in all three contests after his big weekend wins in Maine, Louisiana, Nebraska, Washington and the Virgin Islands. He had edged past Clinton in the race for pledged delegates who formally select a party nominee at a convention in August.
All three of Tuesday's contests occurred in fertile territory for Obama, with large populations of high-income and black voters who have favored the Illinois senator.
Exit polls in Virginia on Tuesday indicated Obama essentially split white voters with Clinton and crushed her 9-to-1 among blacks.
Among Republicans, McCain has built a nearly insurmountable lead in delegates to his party's nominating convention and became the likely nominee last week with the withdrawal of his top rival, former Massachusetts Gov. Mitt Romney.
Exit polls in Virginia on Tuesday indicated Obama essentially split white voters with Clinton and crushed her 9-to-1 among blacks.
Among Republicans, McCain has built a nearly insurmountable lead in delegates to his party's nominating convention and became the likely nominee last week with the withdrawal of his top rival, former Massachusetts Gov. Mitt Romney.
But Huckabee captured two of three contests on Saturday as McCain, an Arizona senator, struggled to win over disgruntled conservatives unhappy with his record on immigration, taxes and other issues.
Obama has 958 pledged delegates to Clinton's 904, according to a count by MSNBC - well short of the 2,025 needed to clinch the Democratic nomination. A total of 168 delegates are at stake in Tuesday's voting.
Clinton, a New York senator and wife of former President Bill Clinton, voiced confidence about her campaign's future even as she looked past Tuesday's three contests and next week's battles in Wisconsin and Hawaii - all of which favor Obama - to focus on crucial March 4 contests in the big states of Texas and Ohio.
Clinton did not wait around for the voting in the capital region, heading on Tuesday afternoon to El Paso, Texas, where she planned an evening rally. She was scheduled to campaign in Texas on Wednesday and in Ohio on Thursday.
Obama also headed out in the afternoon, planning an evening rally in Wisconsin.