IS GOD OMNIPOTENT?

Matthew 19:26  But Jesus beheld them, and said unto them, With men this is impossible; but with God all things are possible. (KJV) Jeremiah 32:27  Behold, I am the LORD, the God of all flesh: is there any thing too hard for me? (KJV) Judges 1:19  And the LORD was with Judah; and he drave out the inhabitants of the mountain; but could not drive out the inhabitants of the valley, because they had chariots of iron. (KJV)

The 'he' in the Judges passage refers to Judah, not to God.  Judah was unable to drive out the inhabitants.  Having an omnipotent being on their side doesn't make Judah omnipotent.  Not a contradiction.