Brian Snyder / REUTERS

New polls show Mitt Romney faces serious challenges in his home state of Michigan.

And PPP breaks it down like this:

Michigan is perceived as a state where Romney really has a home field advantage, but only 26% of primary voters actually consider him to be a Michigander while 62% do not. Only 39% have a favorable opinion of George Romney with a 46% plurality having no opinion about him.  Romney really doesn't have some great reservoir of goodwill in Michigan to fall back on. Only 49% of voters have a favorable opinion of him to 39% with a negative one. That's down a net 28 points from our last poll of Michigan in July when he was at +38 (61/23).

The panel discussed what Romney's up against in the state with No Labels co-founder Mark McKinnon. Here's what they had to say:

Joe Scarborough: There are new polls out now. What does it mean? You’ve got Michigan, which is Mitt Romney’s home state. It’s where he was born. It was his firewall in 2008. It’s where he performed the strongest. Now new polls out today showing that he’s actually getting hammered there…by about 15 points…to Rick Santorum.

Mika Brzezinski: Voters in Michigan head to the polls in less than two weeks, and right now, Rick Santorum has the lead. He edges out Mitt Romney by six points in the latest American Research Group poll. Michigan is the state, of course, where Romney’s father served as governor

Scarborough: And then, of course there’s the Public Policy poll we’ve been hearing whispers about over the past couple days where Santorum’s lead over Romney is even bigger…And the PPP notes that Santorum is ahead of Romney everywhere in Michigan except Oakland County where Romney lived as a child…If [Santorum] wins in Michigan we have to reassess this race completely, don’t we? Do we need to stop calling Mitt Romney the front runner?

Mark McKinnon: Absolutely. And it shows in this day and age with technology and media how little money and organization really mean if you’ve got a powerful message. And this is a true existential threat now for Mitt Romney. If he doesn’t win Michigan, that is a true crisis. I’ve always thought there should be a Gore rule. If you can’t win your home state then you don’t get to be the nominee. You have to go home.

Watch the video below: