It's definately possible, I did it on
888 where they have plenty of daily freerolls. Got up to $71 with a few good high payouts, 1 win and a couple of top tables, but it was a full time grind
The allinners are a pain, and often mean going out early if you challenge them because often even with the best
hands you lose (because too many callers wanting chipped up), so like the previous guy said, avoid them Preflop if you can, no matter what you have. I don't sitout; I tend to sit in, and just fold, because occasionally I can see a flop without going allin Preflop and get chipped up when I have nuts (e.g. Ahigh flush) and they all bet allin into me - so be careful, take your time, and it can be done!
Good Luck!