Besides, the domain name makes sense from a different context: the viewer's. When a viewer in his district goes there, it would be ostensibly be *their* congressman. It's like "MyFreeCreditReport.com" or "MyCorporation.com" or whatever. They're not claiming ownership -- they're offering service for the viewer, with a name relative to the viewer.
Should we sue Intuit because they're claiming ownership of corporations created at mycorporation.com?