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Constraining systematic uncertainties is critical to accurately and confidently use type Ia supernovae as precise cosmological distance indicators. The two dominant astrophysical systematics in optical-based studies are dust reddening and intrinsic color differences. Swift ultraviolet observations of even the most normal type Ia supernovae show a large dispersion in colors comma consistent with contributions from both intrinsic differences and dust reddening. The four sets of high-quality ultraviolet spectra with the Hubble Space Telescope do not yet fully sample this distribution comma but comparisons among them reveal a complexity which requires the contribution of multiple effects. We request a series of ultraviolet spectroscopy of two more type Ia supernovae. These will be chosen based on early Swift photometry to be of the undersampled red variety comma allowing us to measure the wavelength dependence of the intrinsic color and-or host galaxy reddening by comparison with the existing samples. We will determine the source of the differences and constrain the effect they have on the optical measurements used in cosmological measurements. The spectra will also be a significant fraction of the local comparison sample against which we can compare the rest-frame ultraviolet spectra of higher redshift type Ia supernovae.