if($(this).hasClass('phoneNum')){
    var phone_number = $(this.value).replace(/s+/g, '');
    if(phone_number.length > 9 && phone_number.match(/^(1-?)?(([2-9]d{2})|[2-9]d{2})-?[2-9]d{2}-?d{4}$/)){
        //..........do stuff
    }
}