Luck is definitely a factor in poker...
So, we try to eliminate as much as the luck factor as possible, by playing more intelligently an skillfully as possible...
A combination of both I think poker is a game of skill and luck is second, for example today I won my 1 freeroll cardschat at pokerstars I can say that I used both.
I don't think poker is entirely luck, but being on the positive end of variance can definitely help you make more winnings both in cash games and tournaments. There's nothing like going on a heater where you constantly get nuts vs second nuts!
I am sure that any player who considers himself a professional will answer you that the poker game of skill, I am inclined to the fact that no matter what you were not a professional if you do not smile luck is not what skill you will not help. This is my personal humble opinion. I will ask professionals not to persuade me.
If it was just luck why there are wold tournaments with millions in the prize pool... And why there is no roulette tournaments.. luck is a key factor but skill last longer than luck..