When Mrs Clinton accepted the job of Secretary of State many of her supporters feared she was falling into a trap. Fearing that she could be a rival source of power from Capitol Hill, Obama calculated she would be less of a threat if he brought her inside his tent.
The downsides for the former First Lady were obvious. She would give up her cherished seat as Senator for New York, which gave her an independent power base. Her voice on domestic policy would be silenced.
And her fortunes would inevitably be linked to the man whom she fervently believed was not up to the top job.
It is a sign of Mrs Clinton's astuteness that she said yes and now finds herself ideally placed to succeed Mr Obama or, in the increasingly plausible scenario that he becomes a one-term president, the Republican who ousts him in 2012.
Mrs Clinton can afford to be assiduously loyal because her critique of Obama - "a lot of talk, no action" is how she acidly described him in March last year - is already out there and increasingly resonant. She now has unassailable credentials in the one area where she appeared weak in 2008 - foreign policy.
She has been able to stay out of the contentious debates over health care, Wall Street bailouts and the spiraling deficit while her husband, confounding many, has been a low-key apparent model of propriety since she took over at Foggy Bottom.
Two months ago, Mrs Clinton answered, straight-faced, with a flat "no" when asked if she would ever run for president again, even adding that "it never crosses my mind".
Perhaps that patently implausible denial was the surest indication of all that Mrs Clinton is better placed than ever to become America's first female president - and she knows it.
2012 does seem more feasible than it did six months ago, or even three months ago. I think the key will be 0's approval numbers sinking into the thirties and staying there. And it's pretty much a given that the Dems will have their collective a$$es whooped in the midterms, which are just eleven months away.