How to focus cursor on Username textbox once open logon page

@model MvcApplication1.Models.LogOnModel

@{
    ViewBag.Title = "Log On";
}

<script type="text/javascript">
    $(function () { $('#txtUserName').focus(); });
</script>

<h2>Log On</h2>
<p>
    Please enter your user name and password. @Html.ActionLink("Register", "Register") if you don't have an account.
</p>

<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>

@Html.ValidationSummary(true, "Login was unsuccessful. Please correct the errors and try again.")

@using (Html.BeginForm()) {
    <div>
        <fieldset>
            <legend>Account Information</legend>

            <div class="editor-label">
                @Html.LabelFor(m => m.UserName)
            </div>
            <div class="editor-field">
                @Html.TextBoxFor(m => m.UserName, new { maxlength = 23, id = "txtUserName"})
                @Html.ValidationMessageFor(m => m.UserName)
            </div>

            <div class="editor-label">
                @Html.LabelFor(m => m.Password)
            </div>
            <div class="editor-field">
                @Html.PasswordFor(m => m.Password)
                @Html.ValidationMessageFor(m => m.Password)
            </div>

            <div class="editor-label">
                @Html.CheckBoxFor(m => m.RememberMe)
                @Html.LabelFor(m => m.RememberMe)
            </div>

            <p>
                <input type="submit" value="Log On" />
            </p>
        </fieldset>
    </div>
}