Ralof for example, he mentioned he does not like all the things Ulfric says. And he is very helpfull even if you are not a nord. Do you people know any other stormcloaks/stormcloak supporters like this?

Most of them, except for Ulfric and Galmar are like Ralof. They're tolerant of other people, unlike their leaders.
And I guess that an enemy of their enemy is their friend, so most Nord rebels join Ulfrics cause.

Not all nazis wanted to exterminate all the jews in the world (they would be happy just ruling it)

Nevermind this, I never said this.
I don't feel like arguing today.

I can't get myself into being a Stormcloak supporter unless I am playing a Nord. It just doesn't feel right. While on the other hand I can accept the idea of a Nord supporting the Empire.

I do believe that maybe not so much the other human races, but Beast races and Mer seem to be looked down on in general by the Stormcloaks and their supporters.

The stormcloaks only want Skyrim, the nazis wanted the whole world...there is a little bit difference in that

Please stay well away from real life politics and comparisons that are not suitable.

Maybe other races would join the stormcloaks because of their hatred to the thalmor. (the reason why my bosmer is a stormcloak)
Redguards could support the stormcloaks to, since the empire abandoned Hammerfall.

You think so? My first character was a Dunmer mercenary/hitman and he joined the Stormcloaks. First off, he's of Hlaalu descent, an therefore supported the Empire. But when the Empire fell apart and Morrowind was invaded, he felt that the Empire had betrayed his people. He fought for his life against the Lizards and were one of the last to flee for Solstheim.
When he came to Skyrim, he was met by Imperials trying to kill him. Having two causes now, he went on a personal war against the Imperials. Of course, this eventually got him both beaten and imprisoned, so he looked for allies.
When he saw the poverty in the Grey Quarter, he decided he wanted to help these poor Dunmer. So, when he already was hunting Imperials, he might just as well join the Stormcloaks. And he also figured that he could use the influence he gained from being a commander in the Stormcloak army to appeal to Ulfric. And as I roleplay, I play that Ulfric bent a little to his will, granting the Dunmer better lives.

You can justify anything with some imagination.

That sounds like my nord dual blade fighter. She may not be a dunmer or argonian, but she do wants to help them. And she wants to persuade Ulfric for that. She also joined the stormcloaks because her parents were murdered by the Thalmor when she was only six years. :3