Democrat Obama rolls to two big U.S. wins

WASHINGTON (Reuters) - Barack Obama decisively won two moreDemocratic nominating contests on Tuesday, extending hiswinning streak over rival Hillary Clinton and building momentumin a hard-fought U.S. presidential race.

Obama swept to easy victories in Virginia and the Districtof Columbia, U.S. media projected, running his hot streak toseven after five consecutive wins over the weekend andexpanding his lead in pledged delegates who select the party'snominee.

Republican front-runner John McCain was running slightlybehind his last major challenger, former Arkansas Gov. MikeHuckabee, in early Virginia returns as McCain tried to movecloser to clinching the party's nomination for the Novemberelection.

Maryland officials extended voting, which was supposed toend at 8 p.m. EST/0100 GMT on Wednesday, to 9:30 p.m. EST/0230GMT because rain and freezing temperatures created travelhazards throughout the region.

Obama, who would be the first black U.S. president, wasfavoured in all three contests after his big weekend wins inMaine, Louisiana, Nebraska, Washington and the Virgin Islands.He had edged past Clinton in the race for pledged delegates whoformally select a party nominee at a convention in August.

All three of Tuesday's contests occurred in fertileterritory for Obama, with large populations of high-income andblack voters who have favoured the Illinois senator.

Exit polls in Virginia on Tuesday indicated Obamaessentially split white voters with Clinton and crushed her9-to-1 among blacks.

Among Republicans, McCain has built a nearly insurmountablelead in delegates to his party's nominating convention andbecame the likely nominee last week with the withdrawal of histop rival, former Massachusetts Gov. Mitt Romney.

But Huckabee captured two of three contests on Saturday asMcCain, an Arizona senator, struggled to win over disgruntledconservatives unhappy with his record on immigration, taxes andother issues.

Obama has 958 pledged delegates to Clinton's 904, accordingto a count by MSNBC -- well short of the 2,025 needed to clinchthe Democratic nomination. A total of 168 delegates are atstake in Tuesday's voting.

McCain has all but clinched the Republican nomination bywinning more than 700 of the 1,191 delegates needed fornomination -- an overwhelming lead on Huckabee, who has barelymore than 200.

Clinton, a New York senator and wife of former PresidentBill Clinton, voiced confidence about her campaign's futureeven as she looked past Tuesday's three contests and nextweek's battles in Wisconsin and Hawaii -- all of which favourObama -- to focus on crucial March 4 contests in the big statesof Texas and Ohio.

Clinton did not wait around for the voting in the capitalregion, heading on Tuesday afternoon to El Paso, Texas, whereshe planned an evening rally. She was scheduled to campaign inTexas on Wednesday and in Ohio on Thursday.

Obama also headed out in the afternoon, planning an eveningrally in Wisconsin.

(Additional reporting by Deborah Charles, Jeff Mason,Andrew Stern, Caren Bohan; Editing by Lori Santos)

(To read more about the U.S. political campaign, visitReuters "Tales from the Trail: 2008" online athttp://blogs.reuters.com/trail08/)