A year of political media and marketing that seemed to defy precedence is ending, as you might expect, on yet another unprecedented note: an ad campaign thanking the President of the United States for letting Americans say something they were never prohibited from saying: "Merry Christmas."

It is a simple grassroots message paid for by local citizens, expressing their concern about the Presidency. That's what the citizens of a neighborhood in Youngstown, Ohio, say about the ad they kicked in to buy on a local billboard. The content is a one-word message: "IMPEACH."

We may never know the role paid media played in the outcome of Alabama's Senate race, but we do know it likely was one of the most media-contested races of its kind ever when you add up the total media effect, including news media coverage, social media sharing, and a variety of below-the-line guerilla-marketing tactics.

As big a role as social media played in the 2016 elections, it doesn't expect to eat into conventional TV advertising spending, according to year-end outlooks released this week by the leading ad industry forecasters. Given the number of hotly contested races, the 2018 midterm elections are expected to set a new record in conventional U.S. ad spending.