I'm not sure if 40% of 'registered voters' are black and latino, or not - but even if that's so, it's not a 1 to 1 description of how electoral college votes (the votes that COUNT) are assimilated and counted.
Several times we've elected a President who didn't win a majority of the 'popular vote' but did win a majority of the required electoral college votes.
It's why candidates target 'states' more so than ethnic groups, per se ... there are 15 states plus the District of Columbia that have populations (per electoral vote) less than 1/2 of the populations of Texas or California relative to their 'electoral college' voting clout.
It's kinda like the Senate ... EVERY STATE regardless of size has TWO U.S. Senators, all of whom have the same voting weight ... a Wyoming Senator with less than 600,000 residents in the entire state can cancel out the vote of a California Senator who represents a state with 38+ million residents.
National elections aren't about winning the MOST voters they're about winning the most states that when COMBINED win you 270 'ELECTORAL COLLEGE' votes. A candidate could conceivably lose California, NY, Texas, Florida, Ill, NC, GA, Ohio, PA and Michigan ... the 10 largest state by population (BY FAR) - LOSE the 'popular vote' (1 man - 1 vote) by 10-20 MILLION votes and still be elected President of the United States if he won enough of the smaller states.
GA, SC, Texas, LA, MS, TN, AK ... ALL of those 'southern' states have VERY LARGE percentages of their populations made up of 'minority' voters (black and/or latino) but have been dependably 'red' states for decades.
The LARGEST impact minority voters have on 'national' impact elections is in Congressional Districts ... electing the Congress, much more so than electing a President.