They don't know how the election will turn out, so for now they're just 'keeping their powder dry'.
The girls put on their lipstick and (face) 'powder' before heading out to the dance.
The boys decided to 'take a powder' as soon as they saw there was work to be done.
(..) how you feel. Hmm. But that is impossible. Why? You don't need powders and potions, my queen. You don't need lies. You are strong enough to look into the Lord's light and see his truth (..)2014 TvShow: Game of Thrones Title: Mockingbird Season: 4 Episode 7
(..) and you're devoted to the truth. If they're lies, my lady, aren't they best avoided? Not always. Most of these powders and potions are lies. Once they step into his light, they will see the lie for what it was-- a trick that led them (..)2014 TvShow: Game of Thrones Title: Mockingbird Season: 4 Episode 7