Robin Thicke -- Paula Patton is Softening On Reconciliation

Robin Thicke has made significant headway in his campaign to win his wife back, because multiple sources directly connected to the couple tell TMZ ... Paula Patton is open to giving him another chance.

We're told Robin and Paula never stopped communicating. They talk constantly, but she was very clear the day she dumped him ... she wanted a DIVORCE.

Our sources say the tone of the conversations has changed, and the 2 of them are now talking about what Robin needs to do to convince Paula that the marriage can work to her satisfaction.

She has not hired a divorce lawyer, we're told, and has no plans to do so. We're told their phone conversations have been productive. But here's what hasn't been productive ... she's not impressed with Robin's on-stage pronouncements of love.

She is impressed that Robin has been a good dad since the split, seeing their kid when he can and keeping in touch when he's on the road.

As for the tone of the conversations ... we're told "smooth and cordial." We're not exactly sure what smooth means, but you know, they're both very ... smooth.