The Know-Nothing party was a nativist political party that sought to undermine immigrant voting strength. The group was against immigrants and was specifically against Irish Catholic and German immigrants.
The Know-Nothing party, particularly active in the 1840s, was characterized by nativism and aimed to undermine immigrant voting strength. The party rejected the support from new immigrants and did not focus on containing the expansion of slavery. Therefore, the correct answer is C: it wanted to undermine immigrant voting strength.
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