Wiki:
The party's founding members chose the name "Republican Party" in the mid-1850s in part as an homage to Thomas Jefferson (it was the name initially used by his party). The name echoed the 1776 republican values of civic virtue and opposition to aristocracy and corruption. The term "Grand Old Party" is a traditional nickname for the Republican Party, and the initialism "G.O.P." is a commonly used designation. According to the Republican Party, the term "gallant old party" was used in 1875. According to the Oxford English Dictionary the first known reference to the Republican Party as the "grand old party" came in 1876. The first use of the abbreviation G.O.P. is dated 1884. Some media have stopped using the term GOP because they think it's confusing. In 2008, the new Washington state top two primary had Republican candidates competing against GOP candidates in the same races. It is the second-oldest continuing political party in the United States.
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