Mark,
You had mentioned that the Rogue is an "everyday car" and is parked outside.
Unless you only make short frequent trips or drive infrequently, your battery should be able to maintain a healthy state of charge from normal use. However, I'm assuming you have your reasons to want to charge.
1) Use a solar charger with an OBD connector
I recall that VW used to use a solar charger made by ICP Solar. You can plug it to the OBD port and suction cup it to the windshield or just lay it on the dash. Search on ebay shows they sell for around $30+. They're a bit bulky so I'm not sure if this will be too inconvenient for you.
2) Use an OBD quick-connect adapter such as the one made by Battery Tender
I have a Battery Tender Jr battery conditioner for my garaged summer car.
Battery Tender makes a fused quick-connect cable for the Battery Tender series that plugs in to the OBD.
http://www.amazon.com/Battery-Tender-08 ... B007KJ2RZK
I tried checking if CTEK makes a similar one but a brief search didn't yield any results, you could look in to it.
You can always cut up a CTEK quick connect to a Battery tender OBD connector so you can use your CTEK charger instead of having to buy a Battery Tender charger which is plug-n-play with the adapter I linked above.