The poll indicates that the President is supported by 54 percent of the voters, with a 'margin of error' of 3 percent. [=it is possible that as few as 51 percent or as many as 57 percent of the voters support the President]
We are trying to improve medical care for poor families living 'on the margins' of society. [=poor families who are often forgotten or ignored by society]
The business has been operating 'on the margins' of respectability. [=has been operating in a way that is not truly respectable]
(..) Because the banks are too busy getting paid obscene fees to sell these bonds. But wait.... You are the bank You work for the bank, i bet your margins are pretty nice and fat. Let's not talk about my margins by the way. Being nice and fat.... That's a nice shirt, do they make it for men? (..)2015 The Big Short