The battery drain will be significant but you should be able to last a day without a charge. It depends on usage though and other factors such as 4G signal strength.
I'm usually in 4g areas and I leave my 4g on all the time and I don't have trouble making it through a full day with my RAZR Maxx. I used to turn it off and on when I was using it for battery life but eventually got tired of doing it and stopped.
Since I set mine to cdma/lte only from global my battery life is as good as it was on GB. I live in a 4g area and have 4g connectivity all the time.
--bill
I get 15-16 hours with 4g and auto brightness on all day long. My screen on time is around 3.5-4 hours also so I could get at least 2 days if I wasn't on my phone so much