The 1860 election goes to the house - Who Wins?

They are all from slave states. There are a couple (e.g. Henry Winter Davis of Maryland) who might vote for Douglas over Breckinridge. But their whole agenda was to avoid secession. With Bell out, they have the choices of Douglas or Breckinridge, and Breckinridge, and Douglas has no hope. Electing Breckinridge averts secession.
Yeah, but I'm just thinking: the Constitutional Unionists, for the most part, were not Democrats. With no secessions in TTL, they hold the balance of power in Congress. Who do you think they'd rather have as President: the relatively young and vigorous John C Breckinridge who could potentially run for re-election in 1864, or the 20-years-older Joe Lane who'd also start off in a weaker position through being appointed by an even dodgier route than John Quincy Adams? Just saying this might be motive for their delegations to abstain in the House vote as well. (Assuming they can't arrange a deal to elect Bell.)
 
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