WRAPUP 2-Obama plans Iowa trip with victory in sight

(Adds more details throughout, previous EUGENE)

By Jeff Mason

ROSEBURG, Oregon, May 17 (Reuters) - Hoping that a pair of contests in Oregon and Kentucky on Tuesday will allow him to essentially clinch the Democratic nomination, Barack Obama will make a symbolic return to Iowa, the state that launched his underdog bid for the White House.

Polls suggest the Illinois senator will win Oregon comfortably while his rival New York Sen. Hillary Clinton is expected to prevail in Kentucky by a wide margin.

But the Obama campaign expects that when the results from the two contests come in, he will have racked up more than halfof the pledged delegates awarded in the state-by-state contests, making him the likely winner in his battle with Clinton to become his party's nominee to face presumptive Republican nominee John McCain in November.

Neither Obama nor Clinton will have enough pledged delegates to lock up the nomination, but Obama contends that superdelegates -- party leaders and elected officials with their own vote in the process -- should back the leader in pledged delegates.

Obama won Iowa's first-in-the-nation nominating contest in January, beating the former first lady who was the national front-runner at the time and was seen by many pundits as having an aura of inevitability in her bid for the Democratic nomination.

Obama's trip to Iowa offers not only a chance for him to look back on the race, but also an opportunity to look ahead to the potential fight with McCain.

Iowa is expected to be an important battleground state in November because its voters in recent presidential elections have been closely divided between Democrats and Republicans.

IOWA TRIP

An Obama aide played down the idea that the Iowa trip would be a "victory celebration or a marking of what's in the past."

"This is meant to be a look to what's ahead," said the aide, who spoke on condition of anonymity. "Iowa is a key general election state," the aide said, noting it had gone for President George W. Bush, a Republican, in 2004 and former Vice President Al Gore, a Democrat, in 2000.

Clinton has given no indication she plans to drop out of the race before the final voting contests on June 3. Montana and South Dakota vote on that date and Puerto Rico holds a vote on June 1.

Clinton argues her strength in big states like Ohio and Pennsylvania that may be critical in a presidential election make her the best candidate against McCain.

But for two straight days this week, she found herself sidelined as Obama sparred with McCain and Bush over Obama's vow to meet with leaders of hostile nations like Iran if elected.

Bush triggered Democratic outrage on Thursday by saying in a speech in Israel that some politicians would pursue the "false comfort of appeasement" by talking with militant groups such as Hamas and Hezbollah and with Iran.