Most of the #1 chat was giving him up to and including Miami, as he's defending a lot less points than Djokovic. It would have helped a lot if Andy had gone further at the US Open, and if he'd won it, he'd have been within spitting distance of the Race #1, but would still have relied on him stringing together a lot of wins in a row after a lot of wins in a row.
The biggest problem is that Murray has always run out of steam if he goes deep at too many tournaments in a row, while Djokovic normally seems to be fresh week after week. That looked like it might be changing, but he still made it to the finals of the US Open, admittedly with the help of a WO and a couple of retirements. Now he'll have a bit of a break, so it may well be back to business as usual for him during the Asian swing.
In terms of ranking, it will be in Andy's best interests if Argentina win this tie, so he can focus on the points-rich WTF. With Jamie qualified for it too, he'd benefit too.