After McCain's big Ohio VP rally next week comes one in Pa.

Hmmm.

You know how everyone's been talking about how Republican presidential nominee-to-be Sen. John McCain was gonna name his vice presidential running mate at a big rally in Dayton, Ohio on Aug. 29, the day after Barack Obama's acceptance speech to 70,000 of his closest friends in that Denver stadium?

That still seems likely. But now comes word that McCain advance people have approached a minor league baseball stadium in southwestern Pennsylvania about hosting a rally for the Arizona senator the day after the Ohio rally.

That would be the Saturday of Labor Day weekend before the GOP convention opens in St. Paul. So it looks like after the announcement in Ohio, McCain will go on a quick Midwestern tour with his new partner.

The question is, who will that partner be?

Republicans don't win the White House without Ohio. And the newly-uncovered Pennsylvania plans also make political sense. It's a crucial state for Republican hopes and has rich pockets of one-time Reagan Democrats who went for Hillary Clinton in this year's Democratic primary.

But does it mean that its former governor, Tom Ridge, another Vietnam vet and close friend of McCain's, is among the finalists to join him on the ticket?

With this tour McCain's campaign hopes to squash some of the so-called bounce that Obama might enjoy coming out of the highly-publicized Democratic convention.

Details of the new event at the 7,000-seat Consol Energy Park in Washington County -- home of the Washington Wild Things -- are still being finalized, according to sources. But rumors that McCain would roll-out his choice for running mate in Ohio, Pennsylvania and Michigan before he heads to St. Paul, contributed to a swirl of speculation this week over his pick.

The conservative weekly National Review reported that McCain's campaign has been sounding out key state GOP officials around the country "about the consequences" of picking a pro-choice running mate, such as Ridge.

Other names in the mix include former U.S. Rep. Rob Portman of Ohio, former Massachusetts Gov. Mitt Romney, a Michigan native, Minnesota Gov. Tim Pawlenty and even another intimate McCain pal, one-time Democratic vice-presidential candidate Sen. Joseph Lieberman of Connecticut.

The reported responses from many conservatives and the warnings from conservative talkers like Rush Limbaugh toward a McCain-Ridge ticket warn of a revolt in the GOP base should McCain select the former secretary of Homeland Security. And if McCain ends up picking someone more conservative like Romney, he'll reap free plaudits for acceding to the conservative base.

Of course, such a moderate choice could gain McCain support among additional moderates and independents. And the Arizonan didn't get his reputation as a maverick by accident.

Our colleague Josh Drobnyk has more on this unfolding drama over at the Swamp.

--Andrew Malcolm

Photo credit: Mary Altaffer / Associated Press