Removing Style Attribute From Server Control?

Server control code:

<asp:RequiredFieldValidator ID="RequiredFieldValidatorOnlineID" runat="server" ControlToValidate="TextBoxOnlineID" ErrorMessage="Online ID is required.<br />" ToolTip="User Name is required." SetFocusOnError="True" Display="Dynamic" CssClass="validationerror"></asp:RequiredFieldValidator>

Rendered Server control code:

<span id="ctl00_ContentPlaceHolderSYLMainMaster_RequiredFieldValidatorOnlineID" title="User Name is required." style="display:none;">Online ID is required.<br />

I have tried the following to remove the style attribute with no luck:

RequiredFieldValidatorOnlineID.Attributes.Remove("style")

and

RequiredFieldValidatorOnlineID.Attributes.Clear();

I don't need and want the style attribute, how can I prevent it from being written into my code? It messes up the alignment of the error message with my textbox.