The 43rd edition of the marathon is set to include three Olympic medalists and the reigning women's world champion.
Kenya's Wilson Kipsang won bronze in the Olympic men's marathon. His challengers include 2011 Chicago Marathon champ Moses Mosop of Kenya and 2010 New York winner Gebre Gebremariam of Ethiopia.
Ethiopia's Tiki Gelana won gold and Russia's Tatyana Arkhipova was third in the women's race in London. Edna Kiplagat of Kenya won a world title a year earlier.
"Already what we're hearing from people is we went through the 9/11 marathon, and there was never a more moving marathon, and what that marathon did was it unified this city and brought people back to the streets for the first time in weeks," Wittenberg said. "What was most striking about that marathon to me was it was not about running and it wasn't about the runners. It was about the city. And on that day, instead of the fans being there for the runners, the runners were there for the city. And this marathon already has that same feeling."
Jennifer Peltz contributed to this report
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