MADISON, WI (AP)-- A new report says the sand mining and natural gas industries have given Wisconsin candidates nearly $758,000 since 2007, with contributions spiking last year as sand mining took off in the state.
The Wisconsin Democracy Campaign study found the gas and sand mining industries gave candidates a total of $18,762 in 2007 when only five sand mines were operating in the state. Last year the industries gave candidates $413,642.
About 100 mines and processing plants were running in Wisconsin that year.
Demand for silica sand is grown because it's used in hydraulic fracturing, or "fracking," a process that produces oil and gas.
Republican Governor Scott Walker received the most money of any candidate over that six year period, accepting $520,266.