What does it mean to 'move the needle'?

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  • In US politics, 'to move the needle' is to significantly change the opinion polls in the direction of your candidate. 

Origin

  • The expression “moving the needle” first appeared in England during the Industrial Revolution in relation to gauges on steam engines. 
  • During World War II, it referred to aviation gauges. 
  • In business today the term is also used generically to describe making progress.  
  • An alternative origin theory is that the phrase comes from seismology. The movement of the Richter Scale indicates the strength of an earthquake.