The activists are marking the third anniversary of a Supreme Court decision that declared that corporations enjoy the same First Amendment rights to free speech as individual citizens and can therefore spend as much as they want to try to influence elections.
Colorado voters last year overwhelmingly approved a ballot measure seeking an amendment to the U.S. constitution to address the finance ruling. So far, most members of Colorado's congressional delegation haven't brought up that idea.
The Saturday rally starts at the Capitol building. Participants planned to walk to a plaza of the U.S. Federal Reserve.
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