27 months? In 2010 everyone knew the Tea party was a conservative/libertarian movement. During this time, many groups with the term "Progressive" in their name got approval.
Via Washington Examiner:
Internal Revenue Service agents used “Tea Party” as “shorthand” for any group filing for tax-exempt status that the agents thought was dedicating too much time to campaign activities and not just to single out conservative groups, a former top IRS deputy told congressional investigators.
Holly Paz, recently fired from her job as director of the agency’s rulings and agreements office, told congressional staffers investigating the IRS that use of the term “Tea Party” was not a way to single out conservative groups. Rather, the term was used as a synonym for agency’s definition of “campaign intervention,” which, according to the IRS, “includes any activities that favor or oppose one or more candidates for public office.” Groups that fit that description could be denied tax-exempt status, she said.
“It was sort of a shorthand reference,” Paz said, according to a transcript of her interview with congressional investigators. “It’s like calling soda ‘Coke’ or, you know, tissue ‘Kleenex.’ They knew what they meant, and the issue was campaign intervention.”