The Politico news site is reporting that veep contender Mitt Romney will appear with John McCain at his August 31 rally in St. Charles County.

But, in a twist that is perhaps more confusing than intriguing, Mike Huckabee — runner-up for the GOP presidential nominee — will also participate in the event, the Politico’s Jonathan Martin reports.

Since dropping out of the primary and backing McCain, Romney’s stock as a potential No. 2 seems to have ascended gradually.

Huckabee? Not so much, which is why his presence at next week’s rally is curious.

From today’s Politico story:

Missouri was hard-fought territory on Super Tuesday, with each of the three Republicans faring well.  So the event would seem to represent a pre-convention unity rally in a swing state where each has a strong following.   But Huckabee and Romney can hardly stand one another, and Huckabee has warned against selecting his once and perhaps future rival twice this month.

It would take a considerable act of pride-swallowing for Huckabee to stand before thousands of fans and watch as McCain touts Romney as his running mate.

The rally will be held in O’Fallon, Mo., at T.R. Hughes Ballpark, home of the River City Rascals, a baseball team in the independent Frontier League.

Politico reports that country singer John Rich will also attend.

As our own Jo Mannies reported earlier, it’s no surprise that Republicans would chose to stop in St. Charles County in their run-up to their national convention. The voter-rich area is prime GOP country,  and could help swing a statewide victory.