Whatever you do don't try any leverage of the badge against the bumper cover (not that you would)
Are you sure it's not bolted from the inside?
If not then as others have said try from the inside with a punch or similar.
Not being dramatic but to save my paint I'd remove the bumper cover to,work on it from behind, or simply drill thought the badge and break it up and off from the centre.
All depends how well it's stuck down and with what.