According to his Crowdrise site, called Project Gump, Oudersluys is trying to raise $10,000 on his trip for the Hall Steps Foundation -- a group that fights poverty by improving health.
The foundation was started by a couple, Sara and Ryan Hall, who are both professional runners.
"Ryan and I started the Hall Steps Foundation to engage the running community in taking their step towards ending extreme poverty worldwide," Sara Hall told ABC News via email. "It's awesome to see people like Barclay who have shared our vision, and taken a very big step! His efforts are incredibly inspiring and we have been following his progress. Through his efforts he is raising funds and awareness to bring clean water to communities in Mozambique."
Oudersluys usually begins his runs around 6 a.m. and ends between noon and 2 p.m. and runs about 31 to 32 miles a day in around five to seven hours -- rain or shine.
Just like his favorite movie, Oudersluys started his cross-country marathon at the Santa Monica Pier in California in May, and he plans to finish at the famed lighthouse in Rockland, Maine.