If there is one lesson you should take from the dramatic shifts in our Iowa polls over the last two months, it's that things are volatile.

Although a higher percentage of caucusgoers say their mind is made up (30%) now than in September (20%), 69% say they either don't have a first choice or could be persuaded to vote a different way.

There are seven candidates with favorable ratings over 50%.

When you look to history, leaders in Buttigieg's position have lost many times. In caucuses without an incumbent running, the leader in the Iowa polls at this point have only gone on to win the caucuses three of the last nine times since 2000. That means they have lost more often than they have won.

This is especially the case when the leader was polling below 49% like Buttigieg is currently. In each of these six cases, the Iowa polling leader at this point since 2000 went on to lose the caucuses -- and they went on to lose the nomination as well.

Now, that doesn't mean Buttigieg is destined to lose or anything like that. Rather, it's an indication that a lead at this point doesn't necessarily mean a whole lot when there are a slew of well-liked candidates not too far behind.