![Image](https://forums.factorio.com/images/ext/da1074c0c04279625f6f9b74ef7ec1cd.png)
I'm assuming that this is a bug since the cursor turns into an x after you move a certain distance away. You also do not have to be within range to connect the wires.
P.S. just now noticed that you do not receive the wires back after picking up the poles they were connected to, not sure if that is a bug or not.