Illinois was actually surprisingly close, with Lincoln only getting 50.7% of the vote to Douglas' 47.2% without a fractured Democratic Party, that could potentially lead to a Douglas victory. Same with Indiana; Lincoln only got 51.1%.
Illinois + Indiana + the West Coast states + all of New Jersey would be enough to put Douglas over the top.
Indeed, Illinois + Indiana + California to Douglas and Oregon to Breckinridge even with OTL New Jersey division get 149-75-40-39, where 40 is Douglas and majority is 152.
BTW, that is actually the EV breakup used in Schwartz Mirotvor's
The Peculiarities of National Elections - a (really good, IMHO, except that it's, unfortunately, in Russian) Douglas-wins TL (technically, story) with an apparent POD in October 1860 (Lincoln lives up to his nickname and explicitly shows his abolitionist views in a few speeches before the election) and some really weird things later on (I think that's the only TL I've seen where the North
and the South secede - and especially where it makes sense in context).
I think that TL's most major error is on who becomes VP (it, unfortunately, wouldn't be Johnson - by the way, just HOW MANY different Johnsons did the Americans have as VPs or VP candidates? I can list four out of my head, and that's probably not even close to a full list), and that's hardly relevant to the plot, given that his replacement is
John Breckinridge...

And the issue of Douglas' OTL death date seems to be averted by ending the timeline before that...

Which pretty much only leaves the issues of South Carolina never going to Douglas and Lansing Stout choosing Lincoln over Douglas if Lane is VP... except that both are needed to deny Douglas the majority - and even if that happens, Stout is, at least ITTL, voting pretty much last. Which means, it's known to be a 15-16-1 (Li-Do-Br) split, not counting his vote, before the vote itself - and in such a situation he probably would think that Lincoln isn't going to win anyway, so better Douglas/Lane than just Lane. (Of course, it's hard to determine the actual vote order - but TTL's order is correct if the states are ordered by admission date or population, incorrect if alphabetically, and I can't think of other possible orders except random.)
P.S. I know this post looked just like a coat-rack for Pasha's* "brilliant" TL. But it
is a very good TL (at least IMHO), and since Douglas wins there, it's also close to the main topic.
P.P.S. To the OP question: Douglas' VP choice hardly matters in the long run, because the most plausible Douglas-wins POD gets Lane as VP anyway; of course, if the Democrats don't break, that's another thing.
*) Another name for Schwartz Mirotvor; he's called by a lot of different nicknames on the Russian forums (and I don't know his real name) and is pretty much unknown on the English ones.
...So what, how?
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