Final answer:
Thomas Nast, a political cartoonist, created the iconic symbols for both the Republican (elephant) and Democratic (donkey) parties.
Step-by-step explanation:
The person credited with creating the mascot, or symbol, for both the Republican and Democratic parties is Thomas Nast. He was a prominent political cartoonist in the late 19th century. His works for Harper's Weekly popularized the elephant as a symbol for the Republican Party and the donkey for the Democratic Party. These symbols, while often used humorously, serve to represent the parties in various political contexts and are recognizable hallmarks in American politics.
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