Using sum in CDbCriteria

I need to sum a column as I pull it out of a database. My sql query works fine and is as follows:
SELECT User.userName, sum(views) FROM Rant LEFT JOIN User ON Rant.userId = User.userId GROUP BY User.userId ORDER BY views DESC LIMIT 5;

My CDbCriteria is as follows:

		$criteria=new CDbCriteria;
		$criteria->select = 'sum(views), userName';
		$criteria->with = 'user';
		$criteria->order='views DESC';
		$criteria->group = 'user.userId';
		$criteria->limit=5;
		$dataProvider3=new CActiveDataProvider('Rant', array(
			'criteria'=>$criteria,
		));	

I'm getting the following error when I try to loop through the data in my view:
record "Rant" is trying to select an invalid column "sum(views)". Note, the column must exist in the table or be an expression with alias.