Pass Variable to popup DIV

I have a query that builds a list of links. When you rollover the links is shows a popup div that has more information about the link before you click on it.  What I am not sure how to do is pass what item they are rollingover so it displays the correct information in the popup div. Anyone know how to do this? thanks.

//Link code

<CFOUTPUT query="getcalendar" maxrows="5">    
     <CFIF #event_date#  IS NOT "">
          <cfif DateCompare(#event_date#, Now()) is +1>
               <li><a href="../calendar/calendar_info.cfm?proj_key=#proj_key#&id=#id#" onMouseOver="ShowPopup(this);" >#title# #CurrentRow#</a></li>
          </cfif>
      </CFIF>

</CFOUTPUT>  

//ShowPopup code

function ShowPopup(hoveritem) {
   
    hp = document.getElementById("hoverpopup");
    // Set position of hover-over popup
    hp.style.top = hoveritem.offsetTop - 150;
    hp.style.left = hoveritem.offsetLeft - 250;

    // Set popup to visible
    hp.style.visibility = "Visible";
}

//DIV tag information

<div id="hoverpopup" onMouseOut="HidePopup();">
    <cfoutput>
          <span class="headerpop">#getcalendar.title#</span><hr />

           <p>#getcalendar.description#</p>
        <div class="hoverBottom">
       
        </div>
    </cfoutput>
</div>