The Hat Problem

In a distant land far away, there lived a very evil king. When four tourists came from a foreign land, he immediately arrested them and said them that there were to be beheaded. However, the nice queen said to let them go, and eventually the king called the tourists in and said to them a challenge: "You see here I have four hats, two blue and two red. I will blindfold you as I put one hat on your heads, so you cannot see the color of any hat. I will then take three of you into the stairwell, and take off the blindfold. One of you will be on the top, one in the middle, and one in the front. You are only to look forward, and if you talk, turn around, or communicate in any sort of way I will have you executed immediately. If one of you can guess the color of his hat, then all are free to go. If you are wrong, then all are shot immediately. You cannot see your friend that was left in the room. You have one hour." The tourists accept and they do as the king is told. After thirty minutes, one of them goes out and says the color of his hat, and he is right.

Answer following the guidelines below.

[Select a number if the tourist is 100% sure he is right. The tourist numbers are as follows: 1=bottom of stairs 2=middle of stairs 3=top of stairs 4=out of stairs. Assume that in the thirty minutes, everything that could have been figured out is figured]