'Wealth, as Mr. Hobbes says, is power. But the person who either acquires, or succeeds to a great fortune, does not necessarily acquire or succeed to any political power either civil or military. His fortune may, perhaps, afford him the means of acquiring both, but the mere possession of that fortune does not necessarily convey to him either.'

This quote is taken from Chapter 5 of Book 1 of the Wealth of Nations by Adam Smith.

Here he is saying that power doesn't just come to those who have money. They can acquire it with money, but by default haven't the power. It doesn't matter if there is a concentration of wealth, because they don't have political puissance ( I am excluding market manipulation which isn't political).

Off topic:

Of course socialism/communism and fascism/authoritarianism is different. The government/leader/dictator has almost all the wealth, and by default they have the legal power as well.