Citizens United is especially relevant to presidential elections -- it arose directly out of the 2004 and 2008 campaigns.
"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 McCain–Feingold Act..." [1]
In other words, you are wrong about Citizens United, and unpleasant about it.
"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 McCain–Feingold Act..." [1]
In other words, you are wrong about Citizens United, and unpleasant about it.
[1] https://en.wikipedia.org/wiki/Citizens_United_v._FEC