How to create a view to display poll results formatted as a chart?
About this phrase in the question:


  display poll results using 3rd party charting app


To create charts in Drupal, consider the comparison of charting modules as a possible place to start from, to find the module that best fits your needs. That comparison includes the following: "Poll Chart Block displays poll's results in a block, with a selectable chart type, and using the Chart module." So it looks like what you're trying to achieve already exists as a contributed module, no?

Be aware: I'm a new (co-) maintainer of Chart, and the author of the comparison of charting modules.