Final answer:
Levin's anti-immigrant movement achieved notable successes in New England and the Middle Atlantic but couldn't overshadow the antislavery movement. The Readjuster Movement in Virginia, however, did see success uniting poor whites and blacks against elites. Overall, mid-19th century third-party movements had limited impact on the larger political climate.
Step-by-step explanation:
Levin and his supporters had modest success in the mid-19th century. The group made impressive gains during 1854 and 1855, especially in New England and the Middle Atlantic regions. However, their anti-immigrant movement struggled to capture the nation's attention, overshadowed by the more prominent antislavery movement. Meanwhile, political landscapes were influenced by the lack of clear popular mandates and traditional patronage in the presidential elections, leading to weak presidents and legislators who were disinclined to tie their agendas to such presidency.
In Virginia, the Readjuster Movement led by William Mahone proved to be an early successful third-party movement, uniting disenfranchised poor whites and blacks against the planter elite. This movement was an exception in an otherwise fragmented political environment, with most third-party efforts yielding little success at the polls, as shown by the failure of the Free Soil Movement to capitalize on the spirit of reform in the 1848 election.