  The covariant spectator formalism is used to model the nucleon and the
$\Delta$(1232) as a system of three constituent quarks with their own
electromagnetic structure. The definition of the ``fixed-axis'' polarization
states for the diquark emitted from the initial state vertex and absorbed into
the final state vertex is discussed. The helicity sum over those states is
evaluated and seen to be covariant. Using this approach, all four
electromagnetic form factors of the nucleon, together with the {\it magnetic}
form factor, $G_M^*$, for the $\gamma N \to \Delta$ transition, can be
described using manifestly covariant nucleon and $\Delta$ wave functions with
{\it zero} orbital angular momentum $L$, but a successful description of
$G_M^*$ near $Q^2=0$ requires the addition of a pion cloud term not included in
the class of valence quark models considered here. We also show that the pure
$S$-wave model gives electric, $G_E^*$, and coulomb, $G^*_C$, transition form
factors that are identically zero, showing that these form factors are
sensitive to wave function components with $L>0$.
