If Romney wins the PV he will win the election. Republicans have never lost when winning the PV - this is because California tilts so radically dem.
The Republicans have won the Presidency three times while losing the PV. On two of those occasions, they won California. California is only "radically dem" on the presidential level and even then only for the past 20 years.
Throughout most of the 2004 campaign, Bush had a slim but clear lead in the national polls, but the electoral college swung back and forth. So it was plausible that Kerry could have won without a plurality of the PV.
