For Sale at Sedo:
As of August 7, 2015, two live official trademarks (magnets and a voter registration site) were found on USPTO.gov for the exact term
I Will Vote is a generic term, so the voter registration trademark (registered in 2014) is likely not a very strong mark. Typically, generic terms cannot be trademarked for their descriptive meanings -- we are not sure why this one slipped through the cracks.
The above domain was registered in 2011; the trademark not registered until 2014.
Please consult with a trademark attorney or expert for information on how this domain may be used in commerce or even as a public service site.