Not uniformly no.
Both parties were conservative until the 1896 election when Bryan won the dem nomination and brought the populists into the dem party.
This is simply false.
Other then Lincoln I cant think of someone who was not a conservative being the nominee from either the Republicans or Democrats until 1896
That's your argument? So we'll just completely disregard the Barn Burners, the Radical Republicans and many of the ex-Radical turned Liberal Republicans of whom many supported the
nationalization of the railroads as all conservative? While I would agree that none of these were(aside from some Radical Republicans) "left-wing" they most certainly were not "conservative" and to insinuate otherwise is pure ignorance of the time periods politics.