This is one of just three times (the others being 1988 and 2000) that a losing Democrat carried Iowa. Taylor became the first of currently only six American presidents to have never won Iowa since its statehood.
The 1848 election in Iowa began a trend in which the state would vote the same as neighboring Wisconsin, as the two states have voted in lockstep with each other on all but 6 occasions - 1892, 1924, 1940, 1976, 2004, and 2020.
Results
1848 United States presidential election in Iowa[1][2]