How can Republicans win the presidency now?

By Steve Holland

WASHINGTON (Reuters) - A tottering U.S. economy, an unpopular Iraq war, eight years of Republican control of the White House -- it all adds up to a Democratic lock on the presidency in November's presidential election. Right?

Well, maybe not.

Many Democrats and political experts believe the Democrats have a natural advantage this year, with a "throw-the-bums-out" clamor for change sweeping the country after two terms of President George W. Bush.

The warning signs for Republicans are apparent in the turnout numbers so far from some of the early contests in the state-by-state battles to determine which Democrat and Republican will face off in the November election to succeed Bush.

In Iowa, New Hampshire and Nevada, Democratic turnout doubled the Republican tally, suggesting a higher level of enthusiasm on the Democratic side in what is the most wide-open presidential election of the past 50 years.

"I think it's going to be a very steep uphill climb for the Republicans because the Iraq war, while steadied by the surge, is five years old with no end in sight and the economy is headed south," said Cal Jillson, a professor of political science at Southern Methodist University in Dallas.

In the past 50 years, the only time a party has hung on for a third presidential term was when Republican Ronald Reagan won two terms and was succeeded by his vice president, George H.W. Bush, who left office 15 years ago.

But there are plenty of people who think Republicans can beat the historical odds. Take a look at this survey, for instance: