Sara Fischer, Jonathan Swan The Trump campaign has invested most of its advertising budget to date on Facebook, testing thousands of versions of ads per day to maximize its spending. But behind the scenes, a source familiar with the campaign tells Axios, the thinking has shifted: “As everyone can see, we still have strong spending on Facebook, but the percentage of our total media budget [on Facebook] is shrinking.” The big picture: Since the last election, it’s become obvious that all campaigns are at risk of the changing algorithms and policies at Facebook,…
