I forget the exact title of the article (it was the one where the Romney campaign admitted to having a "white strategy" in regards to pushing white turnout through the roof and saying something to the effect of "no Republican presidential campaign will ever try this again") but I do remember one number: 63% of whites would have to vote for Romney in order for him to have a shot at winning.
Since Romney is performing worse than even McCain with Hispanics, as long as Blacks repeat their share of the electorate and the Hispanic share ticks up a percentage point or two and Obama takes >68% of Latinos, he can tie or beat Romney in the popular vote with just under 38% of the white vote.
The Hispanic vote is killing Romney, if he was competitive like Bush in 2004 , he would probably be favored in NV and CO and much closer in NM.
This shows the power of the minority vote, we are really into uncharted territory in American history. Will this eventually produce a white backlash and cause whites to start voting as a bloc .
Only time will tell
