Cause Ferraro and Palin did wonders for the female vote. It just doesn't work that way. It did back in 1960 for JFK and Catholics. Times have changed.
Plus, Rubio is Cuban, and the GOP is going to win the Cuban vote anyway. Doesn't make much of a connection for the Mexicans and Central Americans who are the bulk of Hispanic voters throughout the country.
The GOP had 2 options a decade ago when the Hispanic explosion became blindingly obvious. They could either become pro-immigration reform or resign themselves to permanent minority status, but become like Enron executives and take all the money on the way out. They chose the second option.