This is the start of Kakashi and his 2 buddies arc. Kakashi has his skills. With Lightning blade there aren’t many opponents who can top his skills. Obito has the sharingan, and if he does have an epic plot twist coming up, maybe he can win this match. But until then….Kakashi has this. Kakashi wins.
Update 4/14/2018 Obito has reappeared in the climax of Naruto with all kinds of super powers which put him in a league of his own. Kakashi simply can’t keep up. Obito wins.