I doubt she would.
At a base level, she lost the election to Donald Trump, someone who was a very unfavorable candidate to many( as she was as well). I think she recognizes that there is a large population that does not want her to be president and I imagine she understands that this not going to change anytime soon barring a rapid change and active effort on her part for more of an onscreen presence (i.e. continual presence as a TV talk show host or pundit). That is a variable in its self that could backfire. Plus, I think it would take Donald Trump angering a large portion of his base while his opposition stays intact to weaken the Republican Party. If dynamics are the same as they are now, why would she expect a different result.
She is someone that many people view (right, wrong, indifferent) as part of the establishment and bound by special interests rather than those of the people who will do what she thinks to in order to win or get ahead. This is true regardless of party affiliations.
Plus, she would be 73 years old next election. Trump is actually going to be the oldest president now at age 70. That is not to say she can't run because she is old, just that it is a variable working against her. For that matter, Donald Trump will be 74 and I think odds are there will be a different Republican candidate as well running for president in 2020.
Lastly, she may not want to go through another campaign.
Overall, I think the deck is not stacked in her favor and it would take her actively bolstering her public presence for the next 4 years in combination with maintaining excellent health in conjunction with further Republican Party strife to make her and the DNC feel for that matter she would be a successful candidate.