Would Hillary have won without Comey’s email letter?

[brucejoel99]

No one is certain about whether or not she would've done so, but it seems likely. As 538 put it:

At a maximum, it might have shifted the race by 3 or 4 percentage points toward Donald Trump, swinging Michigan, Pennsylvania, Wisconsin and Florida to him, perhaps along with North Carolina and Arizona. At a minimum, its impact might have been only a percentage point or so. Still, because Clinton lost Michigan, Pennsylvania and Wisconsin by less than 1 point, the letter was probably enough to change the outcome of the Electoral College.

Note that the percentages are referring to a national swing, so a 1% (national) swing doesn't necessarily mean a 1% swing in MI, PA, or WI per se, hence why the best we can do is say "probably."

[brucejoel99]

No, and the fact that Dems continue to tell themselves this for comfort and treat acknowledging her campaign's shortcomings and missteps as some sort of blasphemy is deeply worrying regarding the sort of candidates they'll nominate and campaign moves they'll make in the future.

It's not mutually exclusive to acknowledge her campaign's shortcomings & missteps while also understanding that - as a matter of statistically speaking - the election was literally so close enough that all it'd take was one changed factor to change the end result, even in spite of Hillary's generally poor candidacy.