This property is already listed with a broker. The sellers are under contract with her and if it is a typical Wisconsin listing agreement, if it sells by any means during that listing period, the sellers would owe the agent a commission. So, there is no way for them to sell it to you, without their agent, at this point.
If you do not have a contract with a buyer's agent, you could try to get a reduced price by writing an offer with the listing agent for at least 6% under asking price. Most sellers often put in a 3-5% buffer in the asking price for negotiating and the seller could ask their agent to reduce the commission, since she wouldn't have to share it with another broker. Some agents are able to adjust the commission amount and some aren't, per their broker's policies. My company charges the same amount with or without a buyer's agent, because they feel the listing agent steps in and does the work of both agents (even though they only represent one party.) So, this could work or maybe not - but I always tell my clients - what would it hurt to try? Sometimes, it's worth reducing the commission to get the house sold!
Remember, though - even though the listing agent can write the offer for you and guide you through the steps, she ultimately works for the sellers. But, in Wisconsin, she must keep your confidential information confidential, unless it is a adverse material fact. She also has a legal obligation to give you fair and honest broker services. If you feel confident you can handle the negotiations yourself or can afford an attorney to review the offer - go for it!
Another possibility is to engage an experienced buyer's agent. Many times, we can negotiate a great price for our clients or other seller concessions, which can be a great deal for the buyer. Remember - it's just the "asking price" and it doesn't mean you can't negotiate for a lot less!