  M66 and M96 in the Leo I Group are nearby spiral galaxies hosting Type Ia
Supernovae (SNe Ia). We estimate the distances to these galaxies from the
luminosity of the tip of the red giant branch (TRGB). We obtain $VI$ photometry
of resolved stars in these galaxies from $F555W$ and $F814W$ images in the {\it
Hubble Space Telescope} archive. From the luminosity function of these red
giants we find the TRGB $I$-band magnitude to be $I_{\rm TRGB}=26.20\pm0.03$
for M66 and $26.21\pm0.03$ for M96. These values yield distance modulus
$(m-M)_0=30.12\pm0.03 ({\rm random})\pm0.12 ({\rm systematic})$ for M66 and
$(m-M)_0=30.15\pm0.03 ({\rm random})\pm0.12 ({\rm systematic})$ for M96. These
results show that they are indeed the members of the same group. With these
results we derive absolute maximum magnitudes of two SNe (SN 1989B in M66 and
SN 1998bu in M96). $V$-band magnitudes of these SNe Ia are $\sim$0.2 mag
fainter than SN 2011fe in M101, the nearest recent SN Ia. We also derive
near-infrared magnitudes for SN 1998bu. Optical magnitudes of three SNe Ia (SN
1989B, SN 1998bu, and SN 2011fe) based on TRGB analysis yield a Hubble
constant, $H_0=67.6\pm1.5 ({\rm random})\pm 3.7({\rm systematic})$ \kmsMpc.
This value is similar to the values derived from recent WMAP9 results,
$H_0=69.32\pm0.80$ \kmsMpc. % and from Planck results, $H_0=67.3\pm1.2$
\kmsMpc, but smaller than other recent determinations based on Cepheid
calibration for SNe Ia luminosity, $H_0 = 74 \pm3$ km s$^{-1}$ Mpc$^{-1}$.
