There's no way. The Clintons called in every favor they ever owed to get through this last round and choked. If she entered the race this time, it'd be without all the advantages she had in the previous cycle, tangible and intangible (like coming off of a very successful term as Secretary of State).
No one is going to get out of the race for her, either. If this happens, she'd be one of the 15 or so Dems running, and probably not even an initial frontrunner.
I'd argue that if she were to get in the 2020 primaries with all the potential dem candidates, she'd probably be a close third behind Sanders and Biden. A winnable race if she played her cards right, but no where near as easy as 2016 was.
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