CHICAGO — Two defending champions will highlight the deepest field of elite runners to date when the 33rd Chicago Marathon begins on Sunday.
The field includes Russia's Liliya Shobukhova and Kenyan Sammy Wanjiru. Both won last year's race.
Also expected to race are Steve Jones and Joan Benoit Samuelson, who were Chicago champions 25 years ago. Jones is making a recreational run while 52-year-old Benoit Samuelson is trying to qualify for a fifth straight U.S. Olympic trials in the marathon if she finishes in 2 hours, 46 minutes or lower.
Mayor Richard M. Daley says amateurs will swell the field to 45,000 people.
"We're really fortunate in America to have great business leaders, corporate leaders," said Daley, who was accepted a $500,000 charitable donation for after-school fitness programs from Bank of America.
The bank also said it would honor runners who raise the largest sums for charity with an award named after Daley and his wife, Maggie. Race officials say marathon participants account for up to $10 million in annual charitable contributions.
Elite runners will be competing for portions of a purse totaling $481,000, including $75,000 apiece to the first place male and female winner.
The 26-member women's field include a trio of Ethiopians: Astede Baysa, a two-time Paris champion; Askale Tafa Magarsa, 2008 Berlin runner-up;and Mamitu Daksa, a 2010 Dubai champion. They're joined by Berlin champion Irina Mikitenko of Germany and top American Magdalena Lewy-Boulet.
Among the 23 elite men are Deriba Merga and Feyisa Lilesa, both from Ethiopia. Merga won the 2009 Boston Marathon while Lilesa has a personal best time of 2:05.23, among the fastest in the field.
London champion Tsegay Kebede of Ethopia and Boston winner Robert Kiprono Cheruiyot of Kenya will also challenge Wanjiru.
An estimated 1.7 million spectators are expected to line the course. Temperatures are expected to be in the mid-50s to start and rise into the mid-70s by afternoon, well below the record 89 that caused problems in 2007.