  The sensitivity of the deuteron form factor to contributions from the excited
states of the nucleon is explored using a simple model of the nucleon-nucleon
interaction which employs a tower of charged nucleon resonances. The model is
manifestly covariant, analytically solvable, and gauge invariant. The
consequences of this model are studied in the simplest possible framework. We
assume that all particles have spin zero and that the tower has only three
charged members, which consist of the proton, the Roper, and a higher state in
the vicinity of the $D_{13}$. Nucleon-nucleon S-wave phase shifts and the
deuteron form factor are calculated using this three member tower, and the
results are compared to similar calculations using the proton ground state
only. We conclude that the deuteron form factor is insensitive to the presence
of excited states of the proton unless those states are of sufficiently low
mass to produce strong inelasticities in $NN$ scattering channels.
