How did john adams persuade the delegates to sign the declaration of independence?

John Adams was able to convince the delegates to sign the Declaration of Independence through a speech he gave.  In that speech, he firmly believed that the colonies should be free and that he was willing to give his life for it to come true.  Even if it would be costly in both money and lives, it is worth fighting for.  He further stated that despite risks, it will pave the way to bright future and that their descendants will preserve it.