[Plugin: WassUp] Is it possible to track persistent cookies instead?

I hope I am explaining this properly – I am looking to group together visits from the same browser including returning visits.
The current mode of operation (if I understood correctly) uses a session cookie. I would like to see a visitor that came back from the same browser (assuming he/she did not erase cookies) let’s say over a large period of time (1 year?).

Is this possible?

UPDATE: I cleaned my plugins (there were some remnants of Super-Cache, although disabled) and cleaned the browser cache as well. There seem to be some persistence, but I am not 100% sure – can you confirm?