I run a swamp cooler during summer, but I also have a crapton of electronics in my room. If I ran a dehumidifier, could that counteract the moisture the swamp cooler is putting out?
I realize this OP is 16 years old, but I'm commenting anyway to address several off-the-mark assumptions made about the question that was posed by the OP.
First, there are some situations where an air conditioner is impractical or impossible, such as an interior room, or a room with no windows, or an HOA that does not allow window or through the wall AC units. Comments mocking the request only demonstrate uninformed presumption.
Second, there are several web sites that agree that the proper balance of swamp cooler and dehumidifier settings can provide an optimized humidity and temperature.
For example, I have a garage in a home in central Florida where the humidity ranges between 40 and 55% humidity about 80% of the time and the daytime temp averages around 90 degrees in the summer - in the garage! Swamp coolers work best with humidity below 50%. If I ran the cooler in the garage while the humidity was 50%, after a short time the humidity would rise to 55 or 60% and would lose its cooling efficiency. Lowering the temp down to around 78 to 80 degrees with a bit lower humidity would be a wonderful thing.
If there was also a dehumidifier in near proximity set to kick on at 50% or 55% humidity, a balance of humidity and temperature could be maintained.
I would not expect the swamp cooler to cool off the entire garage but would only use it in close proximity to my work area - for personal cooling, not room cooling.
As for the danger of static electricity, I wouldn't expect that to be an issue above 40% humidity. In fact, the swamp cooler in close proximity to the workbench would assure that humidity would not reach static electricity-inducing levels, while the temperature and humidity in my immediate area would be improved.