Oh! Third partying yourself into fascism is when voters choose left-leaning third party options so hard that the difference in votes could, if they had gone to the Mainstream left leaning party, swung an election in their favor. Essentially, when more people vote for liberal/left policy than conservative, but dilution causes the conservatives to win anyway. Think Al Gore in 2000, when the Florida electoral votes were decided by a margin of less than 1000.