People are being way too harsh on Obama 2008. It's pretty much the closest thing to a modern day blowout we've seen or will see in some time. He expanded the map where appropriate (VA/CO) and even in unexpected places (like IN). The important thing is winning and trying to bring some senators across the finish line, not overextending yourself and screwing up (Hillary 2016).
I don’t think winning margins is everything since fundamentals play a huge part in the margin as well . For example while Reagan won a huge landslide in 1984 , I’d say his campaign was meh and maybe slightly good because he basically matched his approval rating and I’d say Obama’s 2012 campaign was more impressive than Reagan’s 84 one