WASHINGTON -- Democratic presidential candidate Barack Obama praised the U.S. military Monday for curbing violence in Iraq but was unrelenting in his criticism of the war and last year's troop buildup for allowing what he called a deterioration in the fight against al-Qaida and Taliban militants in Afghanistan.

Republican candidate John McCain, who backs the so-called troop surge in Iraq, was telling Hispanic voters, meanwhile, that he -- not Obama -- had earned their trust by championing an immigration reform bill that nearly killed his presidential bid.

Rarely have candidates in a U.S. presidential campaign confronted such a broad sweep of critical issues as this year, when the country is fighting two wars -- one of them vastly unpopular -- and facing a precipitous economic downturn and raging gasoline prices, growing food costs, relentless growth in home mortgage foreclosures and increasing unemployment.

McCain was speaking Monday to the annual convention of the National Council of La Raza, a pre-eminent Hispanic civil rights organization, bidding for votes among America's fastest growing minority by recalling his support for immigration reform. Obama spoke from the podium there on Sunday and unveiled a plan to offer small businesses a 50-percent tax credit for setting up health insurance programs -- an issue of particular concern in the Hispanic community which has been hard hit in the nation's economic turmoil.

The AP-Yahoo News poll showed Obama leading McCain among Hispanics, 47 percent to 22 percent, with 26 percent undecided.

McCain, a senator from the border state of Arizona, saw his White House bid nearly collapse partly from conservatives' anger over his effort to pass comprehensive immigration reform, which opponents branded "amnesty" for millions of illegal immigrants.

"I took my lumps for it without complaint. My campaign was written off as a lost cause. I did so not just because I believed it was the right thing to do for Hispanic Americans. It was the right thing to do for all Americans," McCain said in the prepared remarks.

"I do ask for your trust that when I say, I remain committed to fair, practical and comprehensive immigration reform, I mean it. I think I have earned that trust," McCain said.

While he worked with Democratic Sen. Edward Kennedy on immigration reform, McCain said, "Senator Obama declined to cast some of those tough votes. He voted for and even sponsored amendments that were intended to kill the legislation."

As part of his bid to win votes in the Hispanic community, McCain has also issued a new television ad, titled "God's Children," in which he lauds the military service of Hispanics.

For his part, Obama has accused McCain of abandoning the immigration effort after protests from within his party contributed to the legislation's collapse in Congress last year.

Both McCain and Obama support an eventual path to citizenship for millions of immigrants in the country illegally, although McCain has shifted his emphasis to securing the U.S. border.

Obama, who was speaking Monday at the National Association for the Advancement of Colored People's 99th annual convention in Cincinnati, Ohio, also returned to his opposition to the Iraq war in an article on the opinion page of The New York Times.

He said Iraqi Prime Minister Nouri al-Maliki's call last week to link an agreement on the continued presence of American troops to a timetable for their eventual withdrawal presented Washington with an "enormous opportunity. We should seize this moment to begin the phased redeployment of combat troops that I have long advocated, and that is needed for long-term success in Iraq and the security interests of the United States."

He said American forces had "performed heroically in bringing down the level of violence (since 30,000 additional forces were added last year). New tactics have protected the Iraqi population, and the Sunni tribes have rejected Al Qaida greatly weakening its effectiveness.

"But," he wrote, "the same factors that led me to oppose the surge still hold true. The strain on our military has grown, the situation in Afghanistan has deteriorated and we've spent nearly $200 billion more in Iraq than we had budgeted. Iraq's leaders have failed to invest tens of billions of dollars in oil revenues in rebuilding their own country, and they have not reached the political accommodation that was the stated purpose of the surge."

McCain insists an American victory in Iraq is at hand and would be upended by removing troops too quickly. He has said he would be ready to leave some U.S. forces in the country indefinitely, as in South Korea, Germany and Japan.

Obama was traveling to Europe and the Middle East later this month. He was to be in Iraq for only his second visit since the war began -- which McCain has been quick to contrast with his own eight trips to the country. While in that region, he was also stopping in Israel and, a top Palestinian negotiator said on Monday, the Democrat would also go to the West Bank to meet Palestinian President Mahmoud Abbas.

Palestinian negotiator Saeb Erekat said Obama will travel to Ramallah on July 23.

Speaking in Paris, Erekat said the Palestinians "welcome this meeting." He says if Obama is elected U.S. president, the Palestinians hope "he will stay the course between Israel and the Palestinians in reaching peace."