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Spontaneous Raman scattering with broadband signal collection is used to simultaneously measure the mole fractions of CO2, H2O, N2, O2, and fuel (C3H8) in a spark-ignition engine operating at low load. Both cycle-averaged and single-shot, cycle-resolved measurements of the mixing between residual and fresh charge are made from the beginning of the intake stroke to TDC compression. The measurements are made at twelve locations simultaneously with sub-millimeter spatial precision, which is sufficient to resolve the characteristic scales of inhomogeneity in most cases. Analysis of the spatial covariance functions provides a measure of the noise contribution to the measured mole fractions and, in certain instances, allows the determination of whether the measured composition fluctuations are associated with spatial inhomogeneities or with cyclic variations in overall charge composition.