How would I join a layer to find how many of a certain type of attribute in a polygon

[MorganBarnett]

I have a layer with geocoded points of registered voters that I am joining with the census block data and I would like to show the percentage of each political party in every block group in my county. Party prefence is listed as an attribute in the point feature table.

[JanetBrewster]

If there isn't any corresponding data that links the two layers (i.e. census block id in the points layer), you could try a spatial join.

[MorganBarnett]

Janet
Thank you for your reply. I am spatially joining, however I cannot seem to get the answer that I am looking for. I need the number of each voters in a particular party within each block group

[JanetBrewster]

Is the spatial join working? If so, you should get census block info for each voter -- then you go into the attribute table of what you joined, sort by census block, select one block, then sort by party and count. There's some manual labor involved, unless you're proficient in python....

If the spatial join isn't working, are you joining in the correct order?

[PhillipRofe]

This probably comes a bit late but as I was looking for a similar solution I thought I'd share one just in case it may help someone in the future.

In Model builder use the spatial join tool with census blocks as in the input table and the points as the join table (make sure that you select a ONE TO MANY relationship).

You should then have multiple IDs for the polygons with even more for the points.

You can then use the Frequency tool to sum up the stats from the points that are in the polygons. There will be a join count attribute and this can be used in the statistics box when summing.