I have been very lucky to be part of a group of researchers (including Dan Hopkins, Dan Galvin, Gerald Gamm, John Henderson, Joel Paddock, and Eric Schickler) who have collected just about every available state party platform issued between 1846 and 2017. The platforms are available via a bulk download at https://doi.org/10.7910/DVN/KNOSHL.
Again, I am grateful to be part of the this project. My contribution was, admittedly, small. Collecting state party platforms is a giant pain and I only wish I had access to this when I was in grad school working on my dissertation (it would have saved trips to North Carolina and Minnesota – although the interviews and the travelling were totally worth it). It’s a great example of open access/collaborative research.