  We present optical and near-infrared photometry and spectroscopy of the type
Ia SN 1998bu in the Leo I Group galaxy M96 (NGC 3368). The data set consists of
356 photometric measurements and 29 spectra of SN 1998bu between UT 1998 May 11
and July 15. The well-sampled light curve indicates the supernova reached
maximum light in B on UT 1998 May 19.3 (JD 2450952.8 +/- 0.8) with B = 12.22
+/- 0.03 and V = 11.88 +/- 0.02. Application of a revised version of the
Multicolor Light Curve Shape (MLCS) method yields an extinction toward the
supernova of A_V = 0.94 +/- 0.15 mag, and indicates the supernova was of
average luminosity compared to other normal type Ia supernovae. Using the HST
Cepheid distance modulus to M96 (Tanvir et al. 1995) and the MLCS fit
parameters for the supernova, we derive an extinction-corrected absolute
magnitude for SN 1998bu at maximum, M_V = -19.42 +/- 0.22. Our independent
results for this supernova are consistent with those of Suntzeff et al. (1999).
Combining SN 1998bu with three other well-observed local calibrators and 42
supernovae in the Hubble flow yields a Hubble constant, H_0 = 64^{+8}_{-6}
km/s/Mpc, where the error estimate incorporates possible sources of systematic
uncertainty including the calibration of the Cepheid period-luminosity
relation, the metallicity dependence of the Cepheid distance scale, and the
distance to the LMC.
