I get the fatal error on login page:
Fatal error: Call to undefined function imagecreatefromstring() in /home/**/public_html/wp-content/themes/the-cause/includes/help/tb_login.php on line 32
You’ve chose to have custom background and logo on login page, but your server doesn’t have GD library installed (it is disabled by default on some hosts): http://www.php.net/manual/en/book.image.php – and it is required for custom logo.
So, you can ask from your host to enable it or you can simply disable custom login page styling (under General Options of theme options).
If you can’t access WP completely, then just go to PHPMyAdmin (or whatever is MySQL manager on your host), go to wp_options table and change this data entry:
option_name = wp_login_change, option_value = 0.
Appropriate command for this is:
UPDATE `wp_options` SET `option_value` = 0 WHERE `option_name` = 'wp_login_change'