Emphasizing the need to return government to the people, McCain formally announced his run for the White House before a cheering crowd.
"I will campaign with respect for the dignity of the office I seek and the people I seek to serve," McCain said. "I swear from my first day in office I will do everything in my power to make you proud of your government."
The son and grandson of Navy admirals, reaching this point hasn't been smooth sailing. The retired military pilot's plane was shot down over Vietnam in 1967.
He ejected, broke both arms and a leg and spent five years as a prisoner of war. It's an experience he credits for his love of country and his independent streak.
"What it does is give you a clear understanding of what your goals and missions should be in your life," McCain says.
So the conservative Republican, who backs school vouchers and tax cuts, also bucked the party leadership by imploring Americans to fight for campaign finance reform. "It's a fight to take our government back from the power brokers and special interests and return it to the people," he says.
Now he's bucking political trends again. He's behind Texas Gov. George W. Bush in the polls, and in the all-important money race. But he's banking on a strong showing in primaries early next year, first in New Hampshire, then in South Carolina and the big state of California to turn his political fortunes around.
McCain hopes to prove he has the right stuff for what he calls the toughest part of the job: commander in chief.
"The president is a lonely man in a dark room when the casualty reports come in," he told the New Hampshire crowd. "I am not afraid of that burden. I know both the blessings and the price of freedom."
His speech also revealed his love for America, reports CBS News Correspondent Bill Whitaker.
"It is because I owe America more than she owes me that I am a candidate for the President of the United States," said McCain.
Additionally, he pledged to protect Social Security, cut taxes, veto pork-barrel spending, improve access to the Internet and test the merits of spending government money in private schools nationwide.
But the question is whether that's enough to convince Republicans that he, not George W. Bush, has the best chance to win next year.