User blog comment:Spritydove/Deeper Thought into the Civil War/@comment-4502503-20120614215211/@comment-4976111-20120616022506

While the Bosmer are part of the Dominion, they don't completely like it altogether. Valenwood is just a front for the Dominion, so they wouldn't have any problem helping getting rid of them.

The only reason why the Khajiit are part of the Dominion is because they think they owe the Thalmor some credit, when in fact it keeps them on a safe side from the Argonians (whom, if I recall, they really don't like).

Hammerfell could possibly side with Skyrim either way. In the end, they still don't like the Thalmor any more than the Empire does, so I'm sure they probably keep an aminosity towards the Thalmor.