  Let f be a newform of weight at least 3 with Fourier coefficients in a number
field K. We show that the universal deformation ring of the mod lambda Galois
representation associated to f is unobstructed, and thus isomorphic to a power
series ring in three variables over the Witt vectors, for all but finitely many
primes lambda of K. We give an explicit bound on such lambda for the six known
cusp forms of level 1, trivial character, and rational Fourier coefficients. We
also prove a slightly weaker result for weight 2.
