On Sunday, the real estate mogul will test his appeal to voters outside the GOP heartland by holding rallies in five states that all went for President Barack Obama four years ago.

Democrat Hillary Clinton, by contrast, planned events in Ohio and New Hampshire, traditional battleground states where recent polling has shown her either in a virtual tie or trailing Trump. 

The states Trump plans to visit Sunday include Iowa, which has gone Republican just once in the past seven presidential elections (George W. Bush in 2004);  Minnesota, which hasn't supported a Republican nominee since Richard Nixon in 1972; Michigan and Pennsylvania, which haven't since George H.W. Bush in 1988; and Virginia, whose 40-year run of reliably voting Republican was ended by Obama in 2008 and 2012.