Have you tried looking at www.binstar.org? Type in ggplot in the search bar (I have already done so and it pops up with different options, one of which is a win32 channel. Since I have already looked at it this is what you should type into the command shell:
conda install -c https://conda.binstar.org/bokeh ggplot
I have not tested since I have win64 but this should work
UPDATE: The link above is now broken try this instead
conda install -c conda-forge ggplot
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