  We present high precision, time-resolved visible and near infrared photometry
of the large (diameter ~ 2500 km) Kuiper belt object (136108) 2003 EL61. The
new data confirm rapid rotation at period P = 3.9155+/-0.0001 hr with a
peak-to-peak photometric range (Delta m_R) = 0.29+/-0.02 mag and further show
subtle but reproducible color variations with rotation. Rotational deformation
of 2003 EL61 alone would give rise to a symmetric lightcurve free of color
variations. The observed photometric deviations from the best-fit equilibrium
model show the existence of a large surface region with an albedo and color
different from the mean surface of 2003 EL61. We explore constraints on the
nature of this anomalous region set by the existing data.
