Reuters: U.S. online political advertising could quadruple to nearly $1 billion in the 2016 election, creating huge opportunities for digital strategy firms eager to capitalize on a shift from traditional mediums like television. These firms — mostly small, partisan and based in Washington — have grown in sophistication since the last presidential election in 2012. They are poised to play a much bigger role in 2016 as digital ads assume more importance and change the way political money is spent on advertising.