Final answer:
The Spanish-American War was not caused by President McKinley's desire for reelection but by other factors such as the sinking of the U.S.S. Maine and Spanish atrocities in Cuba.
Step-by-step explanation:
The Spanish-American War in 1898 was caused by several factors, but the option that was NOT a cause of the war was "President McKinley declared war to help his chances of winning reelection." This statement is incorrect because President McKinley did not declare war for personal political gain. The main causes of the war were the belief that the Spanish had sunk the battleship U.S.S. Maine and the accusations of Spanish atrocities in Cuba.
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