Mary Cal Hollis is an American politician. She was a third-party candidate for President of the United States in the 1996 U.S. presidential election, representing the Socialist Party USA (SPUSA) with running mate Eric Chester Hollis and Chester also received the endorsement and ballot line of Vermont's Liberty Union Party, receiving 674 votes (80.1%) in their primary. Hollis appeared on the syndicated radio program Democracy Now! with two other socialist presidential candidates for a discussion and debate. The SPUSA ticket received 4,765 votes in the general election.
She returned in 2000 as the vice-presidential candidate of the SPUSA, running with David McReynolds and receiving 5,602 votes.
She sought the Party's 2004 nomination for President, but withdrew from the Presidential race shortly before the Party's October 2003 National Convention. At the Convention, she competed for the Party's Vice Presidential nomination but lost to Mal Herbert.
Mary Cal Hollis lives in Colorado. She is a native of Pine Bluff, Arkansas.