Democratic presidential hopeful, Sen. Barack Obama, D-Ill., bottom left, and his wife Michelle greet people at the Iris Festival in Keizer, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
A vendor, left, reacts as Democratic presidential hopeful, Sen. Barack Obama, D-Ill., orders soda and popcorn at a concession stand at the Iris Festival in Keizer, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., left, and his wife Michelle order soda and popcorn at a concession stand at the Iris Festival in Keizer, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., bottom center, shakes hands with people at the Iris Festival in Keizer, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., looks at the ice cream selection at Prince Puckler's ice cream shop in Eugene, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., samples ice cream at Prince Puckler's ice cream shop in Eugene, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., second from left, and his wife Michelle, right, poses with employees at Prince Puckler's ice cream shop in Eugene, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
A man show a photo taken with his digital camera as Democratic presidential hopeful, Sen. Barack Obama, D-Ill., right, buys ice cream at Prince Puckler's ice cream shop in Eugene, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., right, and his wife Michelle eat ice cream at Prince Puckler's ice cream shop in Eugene, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., center, and his wife Michelle talk to supporters outside Prince Puckler's ice cream shop in Eugene, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., buys ice cream at Prince Puckler's ice cream shop in Eugene, Ore., Saturday, May 17, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful Sen. Barack Obama, D-Ill., speaks during a campaign appearance in Roseburg, Ore., Saturday, May 17, 2008. (AP Photo/Don Ryan)
Democratic presidential hopeful Sen. Barack Obama, D-Ill., laughs with a supporter during a campaign appearance in Roseburg, Ore., Saturday, May 17, 2008. (AP Photo/Don Ryan)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., sits with his family at Lew's Drive-In after a campaign stop in Milwaukie, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., greets seniors after speaking at Huntinton Terrace Assisted Living Community in Gresham, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., greets guests after speaking at Huntinton Terrace Assisted Living Community in Gresham, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., greets Mary Hubbard, 91, after speaking to seniors at Huntinton Terrace Assisted Living Community in Gresham, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks to seniors at Huntinton Terrace, a senior center in Gresham, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., is introduced to seniors by his wife Michelle at Huntinton Terrace Assisted Living Community in Gresham, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks to seniors at Huntinton Terrace Assisted Living Community in Gresham, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
**FILE** In this Feb 6, 2008 file photo, Democratic presidential hopeful Sen. Barack Obama, D-Ill., addresses the media in Chicago. Barack Obama is dashing full-tilt into the general-election fight against Republican John McCain without waiting for the Democratic marathon to end. (AP Photo/Rick Bowmer,File)
**FILE** In this file photo from Jan. 30, 2007, Sen. John McCain, R-Ariz., left, and Sen. Barack Obama, D-Ill. greet on Capitol Hill in Washington prior to testifying before the Senate Environment and Public Works Committee a hearing on global warming. Barack Obama, the Democratic presidential hopeful, has pivoted into a general-election fight against the certain Republican presidential nominee, John McCain, without waiting for the Democratic marathon to end. (AP Photo/Dennis Cook)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks to supporters at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks at a town hall meeting in Billings, Mont., Monday, May 19, 2008. (AP Photo/Chris Carlson)
Supporters wait for Democratic presidential hopeful, Sen. Barack Obama, D-Ill., to speak at a town hall meeting in Billings, Mont., Monday, May 19, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., arrives at a town hall meeting in Billings, Mont., Monday, May 19, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks at a town hall meeting in Billings, Mont., Monday, May 19, 2008. In response to criticism Monday from Republican presidential candidate, Sen. John McCain Monday, Obama said "Make no mistake about it, Iran is the biggest single beneficiary of the war in Iraq, a war that should never have been authorized and should never have been fought." He added "John McCain wants to double down that failed policy." (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., greets suppoorters at a town hall meeting in Billings, Mont., Monday, May 19, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful Sen. Barack Obama, D-Ill., speaks during a campaign appearance in Pendleton, Ore., Sunday, May 18, 2008. (AP Photo/Don Ryan)
Democratic presidential hopeful Barack Obama, D-Ill., smiles as he jokes with the crowd during a campaign appearance in Pendleton, Ore., Sunday, May 18, 2008. (AP Photo/Don Ryan)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks at a town hall meeting in Pendleton, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., shakes hands after a town hall meeting in Pendleton, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., waves to supporters at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., smiles as he is introduced at a town hall meeting in Pendleton, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., greets supporters after speaking at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., looks out on a sea of supporters at a campaign rally on the banks of the Willamette River in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., greets supporters at a town hall meeting in Pendleton, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks to supporters at a campaign rally on the banks of the Willamette River in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Boaters on the Willamette River gathered along with thousands of supporters to listen to Democratic presidential hopeful, Sen. Barack Obama, D-Ill., in Portland, Ore., Sunday May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Tony B. Conscious, left, leads a cheer in Portland, Ore., Sunday May 18, 2008, as thousands of people arrive at the waterfront to hear Democratic presidential hopeful, Sen. Barack Obama, D-Ill. At center, holding Sen. Obama's book, is Teri McClain from Seattle who was among the first in line for the rally. (AP Photo/Greg Wahl-Stephens)
Mekayla Hall, left, takes a sticker from volunteer Francesca Rossellini in Portland, Ore., Sunday May 18, 2008, as supporters arrive at the waterfront to hear Democratic presidential hopeful, Sen. Barack Obama, D-Ill.. (AP Photo/Greg Wahl-Stephens)
Supporters of Democratic presidential hopeful, Sen. Barack Obama, D-Ill., celebrate being first in line for his campaign appearance in Portland, Ore., Sunday May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., left, reaches out to supporters at a campaign rally on the banks of the Willamette River in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., upper left, greets supporters at a campaign rally on the banks of the Willamette River in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., greets supporters at a campaign rally on the banks of the Willamette River in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., embraces his family, daughter Malia, 9, left, daughter Sasha, 6, and his wife Michelle, as they are greeted by supporters on the banks of the Willamette River in Portland, Ore., Sunday May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., with his daughter Sasha, 6, climbs to a stage as he is greeted by supporters on the banks of the Willamette River in Portland, Ore., Sunday May 18, 2008. Following at right are his wife Michelle and their daughter Malia, 9. (AP Photo/Greg Wahl-Stephens)
Sen. Barack Obama, D-Ill., left, with his wife Michelle holding daughter Sasha, 6, as daughter Malia, 9 stands between, waves to a sea of supporters at a campaign rally on the banks of the Willamette River in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Greg Wahl-Stephens)
Rosanne McCausland holds her 4 month old chihuahua, Barack, as she waits on waterfront of the Willamette River in Portland, Ore., Sunday May 18, 2008, as people arrive to hear Democratic presidential hopeful Sen. Barack Obama, D-Ill. (AP Photo/Greg Wahl-Stephens)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks to people at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Bernita Jenkins, a delegate from Bakersfield, Calif., left, shows her support for Democratic presidential hopeful Sen. Barack Obama, D-Ill. during a meeting of the Democratic Party Convention delegates held in Sacramento, Calif., Sunday, May 18, 2008. The state Democrats met to select the final delegates to the party's national convention, to be held in August in Denver. Five additional superdelegates were also selected with three pledged to Clinton while two went to Obama. (AP Photo/Rich Pedroncelli)
A supporter listens to Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speak at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., waves to supporters after speaking at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Supporters cheer for Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks to people at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., shares a laugh with his wife Michelle as children Sascha, 6, and Malia, 9, look over the menu at Lew's Drive Inn in Milwaukie, Ore., Monday, May 19, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., throws a T-shirt towards the crowd at the Oregon Twilight track meet held at University of Oregon in Eugene, Ore., Friday, May 9, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., holds a baby while greeting students at the Oregon Twilight track meet held at University of Oregon in Eugene, Ore., Friday, May 9, 2008. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., speaks during a rally at the Montana State University in Bozeman, Mont., Monday, May 19, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., waves to supporters at Waterfront Park in Portland, Ore., Sunday, May 18, 2008. Obama is well known for his ability to draw a large crowd. But 75,000? In Portland, Oregon? The sea of people who converged in the park on the Willamette River was the largest rally for the Democratic presidential hopeful to date.(AP Photo/Chris Carlson)
** FILE ** In this April 18, 2008, file photo, Democratic presidential hopeful, Sen. Barack Obama, D-Ill., addresses supporters at a rally in Philadelphia. Obama is well known for his ability to draw a large crowd. The Illinois senator has already seen plenty of eye-popping crowds, including 35,000 who crammed into Independence Park in Philadelphia. (AP Photo/Jae C. Hong)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., exits his plane en route to a rally at the Montana State University in Bozeman, Mont., Monday, May 19, 2008. (AP Photo/Chris Carlson)
Democratic presidential hopeful, Sen. Barack Obama, D-Ill., arrives for a rally at Montana State University in Bozeman, Mont., Monday, May 19, 2008. (AP Photo/Chris Carlson)
