The reason corporations and unions have been able to spend unlimited sums of money on campaign advertising since 2010 is due to the Supreme Court ruling that campaign spending is a form of free speech.
The Supreme Court ruled that campaign spending is a protected form of free speech, as demonstrated in the cases of Citizens United v. Federal Election Commission and McCutcheon v. Federal Election Commission. These decisions allowed corporations and unions to spend unlimited amounts of money on elections based on their free speech rights. This opened the door for a substantial increase in money flowing into elections.
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