Led by Google and Facebook, U.S. digital ad spending is projected to reach $77.4 billion next year, surpassing TV ad spending for the first time, according to eMarketer. Digital ad spending is expected to represent 38.4 percent of total ad spending, while TV ad spending will comprise 36 percent of total media ad spending. The growth of mobile is expected to drive digital to continue its lead over television. “By 2020, TV ad spending share is expected to reach $77.2 billion — dropping its share to one-third of total media ad spending,” reports Variety. “Digital ad revenue will exceed $105 billion, representing 45 percent share.”