Hillary won the democratic nomination because older voters turned out more to vote in her favor. While young voters primaries for Bernie, the overwhelming majority of those voting in the primaries were older.

Like Barack Obama eight years ago, Bernie Sanders captured the vote of younger voters under 30, and they made up a greater percentage of the electorate in 2016 (17 percent) than in 2008 (14 percent). And Sanders fared better among these younger voters, winning 71 percent of voters under 30 (compared to 59 percent for Obama in 2008). Voters between 30 and 44 made up 23 percent of Democratic primary voters, and they were almost evenly divided between Hillary Clinton and Bernie Sanders. In most of the states where exit polls were conducted, the candidate who won the vote of 30 to 44 year olds won the primary. Six in 10 Democratic voters were over the age of 45, and as she did eight years ago, Hillary Clinton won the support of older voters. Clinton won 64 percent of voters between 45 and 64 and 71 percent of voters 65 and older.

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If more youth turned out to vote in the Primaries in an equal or stronger force than older voters, Bernie would have had the nomination.

Regarding Democrats not doing anything to support immigrants, DREAM Act and DACA were ushered in with greater force and an expansion was attempted due to Obama despite Republicans consistently fighting it or Republican Governors suing against it. The expansion was stalled by our conservative Supreme Court, but would have been successful if we had more left leaning judges. General overview. It's not that democrats are not attempting these things, but more so we lack the majorities in Congress and on SCOTUS. There is the potential of more justices retiring in the next presidential cycle and whoever wins has the ability to make the court more right or left leaning which will have an impact on this.