Overturning Citizen's United
Just a little bit of background for those who don't know:
the conservative non-profit organization Citizens United wanted to air a film critical of Hillary Clinton and to advertise the film during television broadcasts which was a violation of the 2002 Bipartisan Campaign Reform Act, commonly known as the McCainFeingold Act or "BCRA".[4] Section 203 of BCRA defined an "electioneering communication" as a broadcast, cable, or satellite communication that mentioned a candidate within 60 days of a general election or 30 days of a primary, and prohibited such expenditures by corporations and unions.
The key part of this case was a 5-4 decision by the Supreme Court with Justices Roberts, Kennedy, Scalia, Thomas and Alito ruling that the BCRA §203 prohibition violated the 1st amendment. And Justices Stevens, Ginsburg, Breyer and Sotomayor dissenting.
It is important to note that Justices Roberts and Alito were appointed by President Bush. In 2000, Ralph Nader said there was no difference between Al Gore and George W. Bush. Now does anyone really think that Supreme Court Justices appointed by Al Gore would have voted on this case the same way that Roberts and Alito did?
Going forward, who will appoint Supreme Court Justices that will overturn Citizen's United? Who will appoint Justices that will restore the Voting Rights Act. Who will appoint Justices who will protect reproductive freedom?
It won't be Donald Trump.