  We present a variational formulation of electrodynamics using de Rham even
and odd differential forms. Our formulation relies on a variational principle
more complete than the Hamilton principle and thus leads to field equations
with external sources and permits the derivation of the constitutive relations.
We interpret a domain in space-time as an odd de Rham 4-current. This permits a
treatment of different types of boundary problems in an unified way. In
particular we obtain a smooth transition to the infinitesimal version by using
a current with a one point support.
