I don't even understand why it's so complicated. On January 30th Liverpool were 4 points up, with a home game to play against a Leicester team in poor form, they were absolutely the favorites at that point in time. Since they they've drawn 4 games while City hasn't dropped a point so City has the lead back.
At this point I'd say it's really close on who the favorite is. City has a point up and a +9 differential in goals so it's kinda like 1.5 points, however City has two tough league games left, within 4 days of each other, and Liverpool only has 1. Personally I'd give the advantage to Liverpool, but it's not a big one.