Base Running

Question
My Situation is this.  A runner on first with no outs.  The batter hits line drive at the first baseman and he bobbles it.  The runner thinks he catches the ball and retreats to first, to find that the ball was dropped.  Instead of continuing his route to second he remains on first base, and is tagged while on the base and then the first baseman touches the base to get the Out that is the result of the batter.

My question is... Is the Runner on first out even though he left first base only to return to the bag, before the force out behind him was made.  Or are both me out like the play was called?

I have always been under the impression that you cannot be tagged out while on a base, unless the runner behind you is actually occupying the same base.

Answer
Jason,

First off, I want to apologize for the delay in answering. I went on vacation and forgot to turn on my vacation notice here.

In your situation, the runner on first base does not have "protection" at first base. Once the ball is hit fair, he is forced to advance to second base. Because of this, being tagged while touching first base would result in an out.

The only time this doesn't occur is if the runner was not forced from his base. For example, if the runner were on second base when the ball was hit, he would not be forced from his base.