CONCORD, N.H. - Sen. Hillary Rodham Clinton powered to victory in New Hampshire’s Democratic primary Tuesday night in a startling upset, defeating Sen. Barack Obama and resurrecting her bid for the White House. Sen. John McCain defeated his Republican rivals to move back into contention for the GOP nomination.

“I felt like we all spoke from our hearts and I am so gratified that you responded,” Clinton said in victory remarks before cheering supporters. “Now together, let’s give America the kind of comeback that New Hampshire has just given me.”

Her victory, after Obama won last week’s Iowa caucuses, raised the possibility of a prolonged battle for the party nomination between the most viable black candidate in history and the former first lady, seeking to become the first woman to occupy the Oval Office.

“I am still fired up and ready to go,” a defeated Obama told his own backers, repeating the line that forms a part of virtually every campaign appearance he makes.

McCain’s triumph scrambled the Republican race as well.

“We showed this country what a real comeback looks like,” the Arizona senator told The Associated Press in an interview as he savored his triumph. “We’re going to move on to Michigan and South Carolina and win the nomination.”

Later, he told cheering supporters that together, “we have taken a step, but only a first step toward repairing the broken politics of the past and restoring the trust of the American people in their government.”