Sure the Republican party had socialists then, just as it has socialists now. It is a mistake to think they had much influence.
Most of the new Republican party were Whigs, like Lincoln. The Speaker of the House was a Whig-Republican. The Republicans were a majority party in the nation, as shown by their dominance in the House. The number of socialists elected was small to non-existent.
“The Republicans were a majority party in the nation, as shown by their dominance in the House. The number of socialists elected was small to non-existent.”
Of course the Republicans weren’t “a majority party” at all, having won the 1860 election with less that 40% of the vote in a four way race.
It was a purely sectional party and didn’t receive a single electoral vote below the Mason-Dixon Line.
The socialists in American politics at the time of the Civil War were the 48’ers who had fled Germany after their failed revolution in 1848. Carl Schurz is a prime example, and he was an early and active member of the Republican Party from the time of its founding as were many of his fellow 48ers. The socialism of the 48ers still echoes on in American politics today in the leftism of regions like Wisconsin were the 48ers settled:
http://comminfo.rutgers.edu/~dalbello/FLVA/activists/48contribs.html