I'd say Flores over-preformed expectations, but mostly that the pitching has been as good as expected with some different members. That kept them around through the injuries, combined with a hot start that included Wright for portions, Duda, d'Arnaud, etc. They added pieces into the deadline to help plug the gaping holes, guys trickled back, and they clobbered the Nats head to head. They're on pace for 90+ wins, so I don't want to say it's only because the Nats suck, that's why they're running away with it, but they'd have been competitive regardless.