In which region was Frémont most successful? Which states in that region did he not win?

Frémont was most successful in the Northwest region. The states where he did not win were Pennsylvania and New Jersey.

Explanation:

John C. Fremont ran as a Republican candidate in the 1856 election. He did not win the election, he lost to James Buchanan. He has the nickname of "Pathfinder" since he led several expeditions during his lifetime. He was also in the military before he started in politics.

He was given a military position by Abraham Lincoln in the Civil War. He was named Commander of the Department of the West. He did several missions without the approval of the president which led to his court martial in 1848.

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