'President-elect Obama ... Wins Ohio, Pennsylvania,' said the homepage of on-line newspaper The Huffington Post.
'The networks won't tell you, but The Page will: Barack Obama will be the 44th president of the United States,' said The Page political blog for Time magazine.
Mr Obama stood on the verge of becoming the first black US president after capturing key states Ohio and Pennsylvania to leave Mr McCain a near-impossible route to the presidency.
The Pennsylvania and Ohio calls left Mr Obama with a projected 207 electoral votes, surging toward the 270 electoral votes needed to clinch the White House.
Adding in California, a traditionally Democratic stronghold with 55 electoral votes, Mr Obama only needed eight more votes from the remaining 16 states.
Pennsylvania represented McCain's best hope of capturing a state that was won by the Democrats in 2004, the central plank of his strategy given that polls he was likely to lose some of Republican states won by President George W. Bush in that election.
US TV networks make projections based on exit polls and early vote counting.
They have called a number of key states but are yet to declare an overall winner.
They became more cautious after the election in 2000 when they wrongly claimed Democrat Al Gore had won the election. After voting controversy, he lost to George W. Bush. -- AFP