The Germans were bankrupt by the Treaty of Versailles, The Nazi's came to power on promises of breaking the treaty. Until we are subject to those type of chains, the comparison is invalid and used for shock value.
It is a valid comparison in terms of the fact that a desperate populace will vote for anybody that promises them relief.
And the candidates making the most grandiose promises often are tyrants.
And YES, it most likely was used for shock value.
But looking at the tyrants we already have ruling over us, a good dose of "shock" is what the populace needs to awaken us to the direction this country is headed.