1. advance something to a successful conclusion
get/bring/push the deal over/across the line
This expression refers to achieving a goal or completing a task successfully. It references the way a competitor must cross the finish line in order to complete a race. For that reason, the term often implies great effort and difficulty, and something that was perhaps achieved by a narrow margin. It is much more common in a professional context rather than a social one, and is often used to express completing a deal or meeting a deadline. A phrase with a similar meaning is 'seal the deal.'