Well, both have their own strengths and weaknesses... If we were to compare them, as I have seen somebody has already done:
Sakura's Strength > Hinata's Strength
Hinata's Speed > Sakura's Speed
However, they use some very different fighting techniques. Both prefer close quarters combat, but as the anime/manga has proved, Sakura's taijutsu skills are very... wild, shall we say? She basically flails at them and hopes to land a hit, because in all seriousness, she only really needs to land one to win in most cases. Hinata on the other hand has coordinated attacks that are precise and obviously seal off chakra points, making any hopes of a successful offence useless. But then again, the gentle fist is quite a fragile fighting technique. I'd say it requires a lot of balance to pull it off effectively. So if Sakura were to punch the ground, and make a massive shockwave, it would throw Hinata off balance and make her life much harder. Also, she needs to rapidly strike Sakura to get her down. And Sakura has been taught as a medical ninja the skills of evasion, so if Hinata were to be slown down and thrown off balance by a shockwave, then Sakura could be able to dodge her attacks. That is if she COULD dodge the incredibly quick attacks of the gentle fist technique.
What I'm trying to say is, the two are very evenly matched. Both have abilities which play into the other's weakness, so I'd say it could be a bit of a stalemate. But in the end, we've seen that Hinata is a much more competent fighter than Sakura many a time in the anime and the manga. So I'd put my vote in on Hinata.