Since it seems Wall Street will not get what it wanted, investors quickly sold off positions. And among the three major U.S. indexes, the best performer closed down. Yes, you read that correctly: The best performer was the Nasdaq, which lost 1.44% of its value today. The S&P 500 was the worst as it lost 1.83% while the Dow Jones Industrial Average (^DJI 0.56%) was cut down by 216 points, or 1.55%. The concern on Wall Street is that former Italian Prime Minister Silvio Berlusconi and his party members will win the election and change the country's political policies toward its own debt and deficit-reduction programs. As part of the European Union, which has assisted in bailing it out in recent months, a change in policy in Italy could have devastating repercussions throughout the continent.

The S&P 500 fell back below the 1,500 mark and now rests at 1,487 while the Dow now sits at 13,784. Only three of its 30 components ended the day up, which leaves us a lot of losers to talk about. This morning, I discussed why UnitedHealth, United Technologies, and Boeing were all trading lower. Click here to read about those companies or stick around to learn about the other four.

Who was down and why?
Shares of Caterpillar (CAT -0.55%) fell by 2.59% today after the news from Europe hit the U.S. markets. The problems from across the pond could really hit Caterpillar, which has been doing fairly well in that part of the world. In the company's most recent sales report, sales increased by 1% in its Europe, Africa, and Middle East region while sales fell by 11% in North America and 12% in the Asia-Pacific market. While Latin America has been the company's best-performing area, with sales growth of 4% in the most recent reading, the company needs Europe to at least maintain its current sales level or profits will surely take a hit.  

Both the Dow's banking stocks also took big hits today. Bank of America (BAC 3.35%) became the index's worst-performing stock after it lost 3.58% while JPMorgan Chase (JPM 2.51%) wasn't too far behind as it lost 2.47%. My Fool colleague Travis Hoium noted earlier today that the problems in Italy could lead to a collapse of the euro and if that were to happen, there would be major consequences for the financial industry. As we saw in the 2007-08 crises here in the U.S., world economies are closely tied together and in most cases the financial industry acts like the thread.

Shares of Microsoft (MSFT -1.27%) ended the day down 1.4% after analyst Brad Reback of Stifel Nicolaus made his opinion known that the company's board of directors needs to begin considering breaking Microsoft into two units. Brad feels a software company and a separate device company would be better suited for Big Softy. He claims that the current structure is reducing innovation, perpetuating inefficient capital allocation, and causing the company to miss revenue opportunities.