Chelsea could overtake Barcelona if they wanted, because one of their obstacles in signing Lewandowski apart from Bayern Munich was holding back the striker a bit as well because Barcelona could not offer a higher price to Bayern Munich. Of course the opportunity is wide open for Chelsea to talk Lewandowski in order to join them. But so far there has been no serious statement from Chelsea.
Chelsea should have realized this from the start, when Barcelona was unable to make an offer that would ensure Bayern Munich let go of Lewandowski, but at this time Bayern Munich did not feel 100% willing to let go of this quality player. Maybe with the finances Chelsea have they should be able to increase the price which can give Bayern Munich a second thought.
But in this case even if Chelsea can still have some obstacles, because Lewandowski's statement is quite clear he wants to be at Barcelona and this is one of the trump cards for Barcelona to be able to attract this player.
Indeed, from a financial point of view, Chelsea is more favored but Lewandowski's desire at Barcelona seems strong enough that it is difficult to prevent this. And the news now that Barcelona also seems to be getting a fairly large amount of money considering there is some news about De Jong and Manchester United getting closer.