WASHINGTON (Reuters) - The New York Times on Thursday endorsed Democratic Sen. Hillary Clinton and Republican Sen. John McCain for their party’s nominations to contest the U.S. presidential election in November.

In selecting Clinton, a New York senator, the influential newspaper’s editorial board said her experience gave her an advantage over her chief rival in the Democratic race, Illinois Sen. Barack Obama, though on the major issues they were not that different.

“Hearing her talk about the presidency, her policies and answers for America’s big problems, we are hugely impressed by the depth of her knowledge, by the force of her intellect and by the breadth of, yes, her experience,” the newspaper said.

During her years in the Senate, Clinton has immersed herself in national security issues and has won the respect of world leaders and many in the American military, the newspaper said, adding that she would be a strong commander in chief.

Clinton is embroiled in a tight nomination battle with Obama, who would be the first African American president if elected. Former North Carolina Sen. John Edwards has been running in third place.

The newspaper urged Clinton to take the lead in changing the tone of the campaign, in which the Obama and Clinton camps have been trading harsh accusations in a bitter public fight.

“It is not good for the country, the Democratic Party or for Mrs. Clinton, who is often tagged as divisive,” the newspaper said.

In backing McCain, the Times editorial board said it had strong disagreements with all the Republicans running for the presidency, but among them the Arizona senator was an easy choice.

McCain’s chief rivals for the Republican nomination are former Massachusetts Gov. Mitt Romney, former New York mayor Rudy Giuliani and former Arkansas governor Mike Huckabee.

“Senator John McCain of Arizona is the only Republican who promises to end the George Bush style of governing from and on behalf of a small, angry fringe. With a record of working across the aisle to develop sound bipartisan legislation, he would offer a choice to a broader range of Americans than the rest of the Republican field,” the newspaper said.

The Times said McCain has shown he has the character to stand on principle, that he was an early advocate for battling global warming and he was one of the first prominent Republicans to point out how badly the war in Iraq was being managed.

” A genuine war hero among Republicans who proclaim their zeal to be commander in chief, Mr. McCain argues passionately that a country’s treatment of prisoners in the worst of times says a great deal about its character,” the newspaper said.

The New York paper said it could not endorse Giuliani, describing the city’s former mayor as a “narrow, obsessively secretive, vindictive man” whose “arrogance and bad judgment are breathtaking.”

Giuliani brushed off the paper’s portrayal when asked about it during a Republican debate in Boca Raton, Florida.

“I think there are some serious ideological differences,” Guiliani said. “That probably was some of the nicest language they’ve written about me in the last six months.”