WASHINGTON (Reuters) - Democrat Barack Obama and Republican John McCain faced the verdict of U.S. voters on Tuesday after a long and bitter struggle for the White House, with Obama holding a decisive edge in national opinion polls.

At least 130 million Americans were expected to vote on a successor to unpopular Republican President George W. Bush and set the country’s course for the next four years to tackle the economic crisis, wars in Iraq and Afghanistan, an overhaul of health care and other issues.

Long lines of people waited to vote at some polls in battleground states, including Pennsylvania, Ohio and Virginia. Polls close in parts of Indiana and Kentucky at 6 p.m. EST and over the following six hours in the other 48 states and the District of Columbia.

Obama, 47, a first-term senator from Illinois, would be the first black U.S. president. Opinion polls indicate he is running ahead of McCain in enough states to give him more than the 270 electoral votes he needs to win.

A victory for McCain, 72, would make him the oldest president to begin a first term in the White House and make his running mate Sarah Palin the first female U.S. vice president.

World stocks rose to a two-week high and U.S. stocks rose on Wall Street with major indices up more than 3 percent.

Analysts have said market prices probably already reflected expectations of an Obama victory. But if Democrats tighten their control of Congress, it may be easier for the new administration to deal with the financial crisis.

Opinion polls showed Obama ahead or even with McCain in at least eight states won by Bush in 2004, including the big prizes of Ohio and Florida. Obama led comfortably in all of the states won by Democrat John Kerry in 2004.

Ian Edwards, 60, said he voted for Obama.

“Very simple,” the chief executive of a small technology company said. “Bad war. Bad economy. Bad reputation overseas.”

Tyler White, in Scottsdale, Arizona, distrusted Obama on taxes. “My parents are in the upper tier of the tax bracket and feel that Barack Obama is not the right fit,” he said.

DAUGHTERS WATCH OBAMA VOTE

Obama and his wife, Michelle, avoided the line at his Chicago polling station as they were let in a side entrance with their two daughters to vote. Poll workers and voters snapped pictures and cheered.

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“Voting with my daughters, that was a big deal,” Obama said afterward, on his way to Indiana for one last campaign event.

McCain, an Arizona senator, voted near his Phoenix apartment before final stops in Colorado and New Mexico.

Seeking the biggest upset in modern politics, McCain said he was gaining. “We’re going to work hard until the polls close,” he declared.

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His running mate, Alaska Gov. Sarah Palin, kept her ballot secret. “I don’t have to tell anybody who I voted for,” she told reporters in her hometown of Wasilla, Alaska.

The race was closely watched in Kenya, where in Obama’s late father’s village of Kogelo, residents held prayers for his presidential bid and for his maternal grandmother, who died in Hawaii this week.

CAMPAIGN THEMES

Both candidates hammered their campaign themes in the race’s final hours, with Obama accusing McCain of representing a third term for Bush’s policies and being dangerously out of touch on the economy.

McCain, whose campaign has attacked Obama as a socialist and accused him of being a “pal” with terrorists, portrayed him as a liberal who would raise taxes.

But he has struggled to separate himself from Bush in a difficult political environment for Republicans, who are trying to hold on to the presidency for a third consecutive term.

Victories in any of the traditionally Republican states where polls show Obama is competitive, including Virginia, Colorado, Indiana and North Carolina, would likely propel him to the White House.

Obama took command of the race in the last month as a deepening financial crisis reinforced his perceived strengths on the economy, and in three debates.

Democrats are also expected to expand majorities in both chambers of Congress. They need to gain nine Senate seats to reach a 60-seat majority that would give them the muscle to defeat Republican procedural hurdles.

That would increase pressure on Democrats to deliver on campaign promises to end the war in Iraq, eliminate Bush’s tax cuts for the wealthy and overhaul health care.