Phil described the possibilities well. I would pull the shifter (unscrew the big nut holding it onto the tranny) and see what the bushing looks like. If it is OK then you are probably getting into gear but it is not staying. You can drive it like that, but may create some wear on the the shift fork by keeping pressure on it. Since you have to go into it anyway I would be tempted to run with it. The only alternative is to pull the tranny, and if you have a complete breakdown you will have to do that anyway, so not much to lose by trying to run with it.

If the bushing is bad around the shifter you might want to look for a replacement before making the trip. Hate to have you damage the internal components because of a bad external component!