They felt they 'had' the win/game 'sewn up'. [=they felt that they were certainly going to win]
She designs her own dresses and 'sews' in her free time.
He scored a touchdown that 'sewed up' the win/game.
(..) caught fire. You think you're on your own? Let me wash it out and help you sew it up at least. Bit of comfort never hurt anyone. We've been sleeping in ditches the last few weeks. I think we can treat (..)2014 TvShow: Game of Thrones Title: Mockingbird Season: 4 Episode 7