No, in 1861 there was no proposal by Republicans to free slaves by fiat, or by any other method.
What Republicans wanted in the 1860 election was to prevent the expansion of slavery into Western territories and Northern states -- a modest agenda certainly.
But that was plenty enough to drive Fire Eaters to declare secession, Confederacy and, after Fort Sumter, war on the United States.
Proposals to emancipate slaves came out of the Civil War itself, first in response to African-Americans as "contraband of war", and then at the end with the 13th, 14th & 15th Amendments.
But since the time of Thomas Jefferson there were proposals advanced for a Federal buy-out of slaves and voluntary (or involuntary) repatriation to Africa or the Caribbean.
Congress even supported re-colonization of freed-blacks with funds in 1819, but the project proved more expensive than expected.
Proposals for government buy-outs of slaves were never accepted by slave-holding politicians.
The Republican party EXISTED to free the slaves. Don't confuse a legislative proposal with a party platform.
It can be compared to "gun control". Everyone knows that the ultimate aim of the gun controllers is to ban civilian possession of firearms (only the police and the military should be allowed firearms). Any legislation passed in the interim is "a good step forward".