If Sarah Palin chooses not to run for President it would create a big opening for Michele Bachmann to rally the hard right Republican primary voters around her candidacy according to the latest PPP polling.

In Oregon Bachmann gets 29% to 28% for Romney, 10% for Ron Paul, 9% for Newt Gingrich, 7% for Herman Cain, 6% for Tim Pawlenty, and 2% for Jon Huntsman. In Montana she leads with 25% to 22% for Romney, 11% for Gingrich, 10% for Paul, 9% for Pawlenty,8% for Cain, and 4% for Huntsman.

In both states Bachmann’s support is built on strong support from the far right. In Oregon moderates prefer Romney over her by a 39-15 margin and ‘somewhat conservatives’ ones favor him by a 29-22 margin as well. But with ‘very conservative’ voters, which constitute the largest share of the primary electorate at 44%, Bachmann leads 37-26 and that fuels her small overall lead. It’s a similar story in Montana. Romney leads 21-13 with moderates and 26-22 with ‘somewhat conservative’ voters. But Bachmann is up 34-19 with ‘very conservative’ voters and with their constituting 39% of Republican voters that gives her the upper hand overall.

If Palin does run she and Bachmann would end up splitting much of this hard right vote potentially helping Mitt Romney.

There is clearly a large enough base of very conservative voters that if a single ultra-conservative candidate can rally them they would be a real force in the primary. The issue though is that Bachmann and Herman Cain already competing for these votes and if either Palin or Rick Perry get in the race they would be drawing from this same pool.

Romney’s best path is to hope for a very large field and for now focus on preventing candidates like Jon Huntsman, who might also be able to eat into Romney’s moderate Republicans base, from gaining traction.