Twenty Eleven – specific post should stay on page one

On my blog (thomas-reimann.com) I want to realize that I can tell a specific post to stay on the first page.

For example pointing out one post, it goes down with every new post like normal, if it reaches the last position of the first blog page, it should stay there until I remove the marker.

I use the twenty eleven Theme and there is this sticky/featured post option, but this option keeps the post at the very first position.
I don’t need that function, is there a chance to use this option for my request?

So, the option would be ignored until the post reaches the last position from the first page and stays there until I remove the sticky flag. until then it seams like a normal post, stepping down the page with every new post published.

I hope one understands my demand.
Thanks in advance