Obama won by less than 7.8 in 2008; Bill won by 8.5 in 1996, Reagan by 18% in 1984, etc. 2008 was decisive, but not a landslide. And Clinton, Reagan, Nixon all won by more their second time than their first time. As did Ike, FDR too.
In the first place, in 2008, Hillary had a shot of winning the blue wall states (something that Bill Clinton built, and all Obama did was piggyback off) plus states Bill won that Obama got smoked in, like WV, LA, KY, TN AR, as well as standard swing states like NV, FL, OH, formerly MO as well. Now, WV, LA, AR, TN, and KY are out of reach for the Dems both because of Trump but also because of Obama’s divisiveness when talking about race, tho yea maybe Obama suffered in those states because of racism itself. Yea Hillary '08 might not have won that electoral vote in NE, but who cares.