If you have an actual pro-German USA president, that could be enough, even though i have not likely candidates.
Early in WW1, it would be very hard to have the USA with the Central Powers. Later in the war, if Germany does not ever do unrestricted submarine warfare and not shoot ships like the Lusitania, then maybe the British Blockade might eventually drive the USA to the CP. But, it took til 1812 for the USA to get angry enough about British Policy during the Napoleonic Wars. So this one is hard to achieve.
It helps a lot to have some Entente outrage that sells newspapers. The USS Maine lead to war with Spain largely due to Hearst and other newspaper men. There are no likely outrages, but war has strange events such as a German cruiser being capture by the Russian Navy and the code books is not destroyed and the Germans don't change the codes after having a ship captured.
Types of Outrages that might help:
1) British Warship fires on US Warship by mistake.
2) USS Warship explodes in British Harbor.
3) British send back diplomatic reply to Wilson that Wilson sees as insulting.
4) Some outrage on the Western Front that the papers can run with, such as maybe a British Artillery Unit shelling something historic by mistake. The New York Times spends a lot of time talking about one Cathedral in Rheims that the German shelled.
5) UK invades Denmark as shortcut to get to Germany.
6) Japan is felt to be threatening the Philippines. So a bombastic, nationalistic Japanese leader would help a lot.
It was a slow process of the USA going to war with the Entente, and many items contributed, so it is likely a bunch of little things that would cause it to go the other way.
US complaints with Entente:
1) Blockade cause USA to lose business.
2) Poles not Free.
US complaints with Germany.
1) Submarine warfare.
2) Poles not free.
3) Belgium Invaded.
4) Lusitania.
5) Damage to Rheims Cathedral, other historical buildings in France.
6) Wilson found the German diplomatic replies insulting, but not the British ones. Reading them a 100 years later, it appears to be much ado about nothing, but if Wilson felt slighted, it is huge.
If there are more complaints against the Entente than the CP, then it could go the other way. Germany PR is real bad, I am reading the New York Times on WW1, and from the paper alone, one would think Germany was burning Polish towns, when it was really more the retreating Russians. Also, in Galicia, the New York Times says that Russian wartime martial law is more just than AH peacetime administration.