Herman Cain has surged to the lead in Iowa in a new poll, while Mitt Romney is second and Jon Huntsman continues to struggle.

The Public Policy Polling survey has Cain with 30% support, followed by Romney with 22%. Ron Paul is now in third place with 10%, and Rick Perry has fallen to 9%.

Better news for Cain even than his lead is that his supporters are much more solidly committed than Romney's. 50% of them say they will definitely vote for him compared to only 34% who say the same for his co-front runner.  When you look at the race just among voters who say they are firmly committed Cain's lead expands to 19 points at 38% to 19% for Romney, 13% for Paul, and 12% for Perry.

Cain's building his lead off the most conservative elements of the Republican Party.  Romney actually leads with both moderates (25-23) and voters describing themselves as 'somewhat conservative' (33-22). But Cain is completely destroying Romney with 'very conservative' voters, 40-11, and that's what gives him his overall advantage.

Cain is up 39-14 on Romney with Tea Party voters and digging deeper on those numbers you see one of the biggest issues Romney is having to contend with. 53% of Tea Partiers think Romney's too liberal to only 36% who describe him as ideologically 'about right.' Cain has no such perceived ideological problem with those voters- 79% describe him as 'about right' to just 7% who think he's too liberal.

Bad news for Huntsman in the poll, he only had three supporters pick him at the top of the GOP field. Not 3% - 3 people. Ouch!