TV vs Digital political media spend is the argument that never ends. But this cycle the allocation math became more complicated as record levels of campaign cash sought places to go and these options went further downstream into even more local campaigns. Digital channels became more central to campaign organizations and spend, especially in the fight for younger voters, At the same time addressable TV, OTT and data-infused linear buying helped the TV plan evolve beyond spray and pray. What did allocation look like in the last cycle and what did the campaigns learn? Are we any closer to attributing media more accurately and capturing those evolving media habits?

Automated, dynamic and data-driven advertising on a massive scale on Facebook in particular was the breakaway digital story of 2016. But amid growing controversy around how these platforms were abused and gamed by bad actors, legit campaigners now face new rules. Account verification, political ad flagging, stricter policing of accounts and shares, public ad archives have all changed the channel. Key media buyers in the space assess whether and how these changes impacted their social strategy - where and how they allocated, the creative they deployed, and the ways they worked with the platforms.

A new generation of peer-messaging apps for campaigns took political marketing to an entirely new and intimate level this cycle. Questions emerged immediately about their legality, let alone debates about their effectiveness in recruiting or alienating constituents. What did we find out? About the new channel's impact on fundraising? On turnout? On its effectiveness in finding pockets of voters invisible to email and TV? About voter response?

Cross-channel digital campaigns are only as good as the voter identification data and profile used to target them. How have campaigns evolved their harvesting of voter data to ensure a richer and more relevant set of data points? Which channels and appeals are netting richer data? And on the targeting side how are campaigns best penetrating walled gardens to effectively find their voter list and identify persuadable prospects? Everyone promised laser targeted campaigns with fresh, reliable data. But what data is proving of real value in the political ad market?

The human field operation's ground game remains the heart of GOTV strategy. But how are digital channels helping best to make the human channel more efficient and complement those efforts to reach other voters? Text messaging, mobile apps and alerts, targeted Web and mobile ads, email and even social shares were employed this cycle to get supporters to the polls. What worked?