Display DropDownList item at right hand side of DropDownList in ASP.Net

i am using html dropdown list, i want to open dropdown at right hand side on mouseover or onclick.

<asp:DropDownList ID="DropDownListID" runat="server">
    <asp:ListItem Text="static item 1" Value="1"  />
    <asp:ListItem Text="static item 2" Value="2" />
    <asp:ListItem Text="static item 3" Value="3" />
</asp:DropDownList>