The Chamber also compiled kind words about Brunner from four local Missouri business owners whom it said were supporting Brunner's candidacy.

Keith Witt, a farm owner in Warrenton, Mo., said Brunner understood that like other industries, farming needs the government — and McCaskill — to get out of its way. 

"Having John Brunner as Missouri's next U.S. senator would be a welcome change for the farmers who work hard to keep agriculture the No. 1 industry in our state," Witt said in a statement.

The Hill rates this race a toss-up.