Victorious McCain turns sights on Democrats

DALLAS (Reuters) - Republican John McCain turned his sights on his Democratic rivals on Tuesday after claiming his party's presidential nomination, challenging them to explain how they would end the Iraq war without making it worse.

McCain, in a victory speech after winning nominating votes in Texas, Ohio, Vermont and Rhode Island, highlighted the war in Iraq, the economy, and energy independence as key areas that he will focus on in a general election against an as-yet undetermined Democratic opponent.

"Tonight, my friends, we have won enough delegates to claim with confidence, humility, and a great sense of responsibility that I will be the Republican nominee for president of the United States," McCain said to applause in a Dallas hotel ballroom decorated with red, white and blue balloons and two large American flags.

In his speech, he quickly turned to issues he will face in the November presidential election against either Barack Obama or Hillary Clinton, particularly the unpopular Iraq war.

McCain, 71, has taken criticism from the Democrats for saying the United States might be in Iraq for 100 years, a statement he later said should be seen in the context of ongoing U.S. troop deployments in South Korea and Japan.

Under fire from Democrats for supporting the war, McCain tried to turn the tables, saying the next U.S. president must explain how to bring the Iraq war to its "swiftest possible conclusion" without worsening regional instability.

"The next president must explain how he or she intends to bring that war to the swiftest possible conclusion without exacerbating a sectarian conflict that could quickly descend into genocide, destabilizing the entire Middle East," he said.

Obama and Clinton have pledged to start bringing troops home in 2009. McCain has said U.S. troops must stay until Iraq is sufficiently stable to bring the troops home.

He said he would defend the decision to remove late Iraqi leader Saddam Hussein from power while at the same time criticizing the Bush administration's botched war plan.

McCain, flanked by his wife, Cindy, also said he would help repair the ailing U.S. economy and strengthen job growth by pushing lower taxes, less government regulation and resisting trade protectionism.

He took a dim view of an argument that flared up between Clinton and Obama in Ohio over trade.

"I will leave it to my opponent to claim that they can keep companies and jobs from going overseas by making it harder for them to do business here at home," he said.

In a general election that will pit him against a historical opponent -- either a woman in Clinton or a black man in Obama -- McCain, who would be the oldest candidate to be elected to the nation's highest office, reflected on history.

"We're the world's leader," he said. "And leaders don't pine for the past and dread the future. We make the future better than the past. We don't hide from history. We make history."

McCain travels to Washington on Wednesday for an endorsement from President George W. Bush after having lunch with him at the White House.

(Additional reporting by Steve Holland in Washington; editing by Stuart Grudgings)

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