One would normally think that had the race been between Lincoln and a single Democrate opponent then the outcome may have been different. But when you look at the results Lincoln recieved at least 51% of all the votes cast in each of the Northern states. All the votes for Democrates combined did not equal as many as Lincoln got. The Democrat candidate, no matter whether it was Douglas or Breckenridge, would not have won the electoral votes in the North necessary to defeat Lincoln.

My question is why did Lincoln get so many votes? Why was he such a dominate candidate?

That vote told the southern people that they didn't stand a dog's chance of reaching a reasonable solution.