References

30 in 100 eligible voters are now millennials; 6 of those 30 will vote in the 2018 midterms. 55 million millennials expected not to vote in 2018.
Voting age population in 2016: 250m (estimated voting eligible population: 230m)
http://www.electproject.org/2016g

Why Millennials didn’t vote in 2016:
http://data.voterparticipation.org/wp-content/uploads/2017/09/A-Demographic-Profile-of-the-RAE-in-2016-1.pdf page 119

Drop-off among Millennials is predicted to be 54.1% (or 17.2 million voters)
http://data.voterparticipation.org/wp-content/uploads/2017/07/Report.VPC_.Drop-Off.fi_.2017.06.29.pdf page 6

CPS Turnout rates:
https://docs.google.com/spreadsheets/d/1l5fpK7ysQhQbZPv9hnZ_-PO1J1zBVPXSSQjNejTXecY/edit#gid=1189109697

What share of vote might Millennials have in 2018?
http://www.electproject.org/home/voter-turnout/demographics
https://www.nytimes.com/2017/09/14/upshot/how-much-can-the-youth-vote-actually-help-democrats.html

1 in 4 ballots cast in 2016 (25%)
Expected 1 in 10 ballots cast in 2018 (10%)
http://www.pewresearch.org/fact-tank/2017/07/31/millennials-and-gen-xers-outvoted-boomers-and-older-generations-in-2016-election/

Millennials believe the U.S. is moving in the wrong direction. However, they still see engaging with institutions, including government (through actions like voting and petitioning), as a way of creating positive change for the causes and social issues they care about. 77% say that voting is the duty of every citizens.
http://www.themillennialimpact.com/sites/default/files/reports/Phase2Report_MIR2017_091917_0.pdf

Millennial “slacktivisim” 37% signed an online petition.
https://www.prri.org/spotlight/millennials-political-slacktivism/