OnClick not firing in UserControl when button is clicked

I have a master page. In the master page I have a UserControl for the footer. In the footer I have a button that is not firing OnClick. During debugging I see the function being called by OnClick, btnSignup_Click, is not getting hit. I can't seem to figure out where the mistake in my code is.

master.master

<%@ Master Language="C#" AutoEventWireup="true" Inherits="master" Codebehind="master.master.cs" %>
<%@ Register TagPrefix="xyz" TagName="Footer" Src="~/controls/footer.ascx" %>


<xyz:Footer ID="Footer" runat="server" />

footer.ascx

<%@ Control Language="C#" AutoEventWireup="true" Inherits="footer" Codebehind="footer.ascx.cs"  %>

<div>
     <asp:TextBox ID="fName" runat="server"></asp:TextBox>
     <asp:RequiredFieldValidator ID="RequiredFieldValidatorfName"  ValidationGroup="validationSignup" Display="Static" ControlToValidate="fName" ErrorMessage="First Name required" runat="server"></asp:RequiredFieldValidator>
</div>

<div class="button">
    <asp:Button ID="btnSignup"  CommandName="Button" runat="server" ValidationGroup="validationSignup" Text="Signup"  HeaderText="Please fill in all required fields before continuing." OnClick="btnSignup_Click"/>
</div>

<div class="validationSummary">                 
    <asp:ValidationSummary ID="ValidationSummary"   ValidationGroup="validationSignup" runat="server"></asp:ValidationSummary>
</div>

footer.ascx.cs

public partial class templates_site_footer : BaseUserControl
{       
    protected void Page_Load(object sender, EventArgs e)
    {
        btnSignup.Click += new EventHandler(btnSignup_Click);
    }
    protected void btnSignup_Click(object sender, EventArgs e)
    {       
        if (!Page.IsValid)
            return;

        // code to execute after button is clicked
    }
}