McCain clinches

Sen. John McCain, R-Ariz.

The race for the Republican nomination for president is finally over, as Arizona Sen. John McCain secured enough delegates to win the top spot on the ticket.

"The contest begins tonight," McCain said in his victory speech, referring to the upcoming battle against a still-to-be-determined Democratic opponent.

"I want to thank all of you here and all the Republicans, independents and independent-thinking Democrats, in all parts of the country, who supported our campaign for the nomination and have brought us across the finish line first, an accomplishment that once seemed to more than a few doubters unlikely."

Former Arkansas Gov. Mike Huckabee, who had refused to suspend his campaign, finally called it quits and phoned McCain to inform him of his decision.

"I extended to him not only my congratulations, but my commitment to him and to the party to do everything possible to unite our party, but more importantly to unite our country, so that we can be the best nation we can be – not for ourselves, but for the future generations to whom we owe everything, just as we owe previous generations all that they have done for us," Huckabee said.

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McCain noted in his speech: "Now we begin the most important part of our campaign: to make a respectful, determined and convincing case to the American people that our campaign and my election as president, given the alternatives presented by our friends in the other party, are in the best interests of the country we love. ... Our campaign must be, and will be, more than another tired debate of false promises, empty sound bites or useless arguments from the past that address not a single American's concerns for their family's security."

Huckabee said McCain was an honorable man who had run an honorable campaign, and said he had kept the faith in his campaign, which came from relative obscurity in 2007 to national prominence in recent months.

"I'd rather lose an election than lose the principles that got me into politics in the first place," Huckabee added.

McCain, 71, gained the 1,191 delegates needed to win the GOP nomination with a series of primary victories. President Bush has invited him to the White House tomorrow for a show of support.

McCain's campaign had been considered on life support before the primary season began, with many Republicans blasting the senator's perceived stance giving amnesty to illegal aliens.

Former Bush adviser Karl Rove, now a political consultant for the Fox News Channel, predicted shrinking news coverage for McCain in coming months now that the nomination race is over.

When asked how he'd advise McCain to stay relevant, Rove answered: "He needs to find big things that he can go and talk about, and he needs to carefully schedule those big things to talk about in states where it's important and at times he might be heard."

This is McCain's second run for the White House, after his loss to George W. Bush eight years ago.