Issues of importance to 38 non-battleground states are of so little interest to presidential candidates that they don’t even bother to poll them individually. 

Charlie Cook reported in 2004: 
“Senior Bush campaign strategist Matthew Dowd pointed out yesterday that the Bush campaign hadn’t taken a national poll in almost two years; instead, it has been polling [the then] 18 battleground states.”

Bush White House Press Secretary Ari Fleischer acknowledging the reality that [then] more than 2/3rds of Americans were ignored in the 2008 presidential campaign, said in the Washington Post on June 21, 2009: 
“If people don’t like it, they can move from a safe state to a swing state.” 

Over 87% of both Romney and Obama campaign offices were in just the then 12 swing states.  The few campaign offices in the 38 remaining states were for fund-raising, volunteer phone calls, and arranging travel to battleground states