The only thing getting grilled at John McCain's Arizona ranch this weekend is the ribs, despite speculation that the McCain's heavy-hitter guest list at the Memorial Day barbecue will be auditioning for the Republican vice presidential post.

Not everyone on the list of potential running mates made it to the weekend cook-out. Former Homeland Security Secretary Tom Ridge, former Arkansas Gov. Mike Huckabee and Minnesota Gov. Tim Pawlenty weren't there, but a host of potential running mates were, and each has something to offer.

Former Massachusetts Gov. Mitt Romney could bring in conservative votes and cash, but he and McCain would have to take back a lot of what they've said about each other during the primary campaign.

Louisiana Gov. Bobby Jindal might steal some of the youth aura from Barack Obama, as Jindal is half of McCain's age and younger than Obama. However, that could also be his disadvantage, as Republicans try to argue Obama's inexperience is a downside to his candidacy.

Gov. Charlie Crist is a popular moderate in Florida, and he helped him win the state. But McCain may need to shore up the other side of his party.

The official word from the McCain camp -- and repeated by another man on the guest list and someone also discussed in political circles as a possible vice president, South Carolina Sen. Lindsey Graham -- is that this weekend's event is just a party and everyone should calm down.

"This was purely social. Anyone who know John knows he is like a kid at Christmas showing off ranch. It's just his friends in the business world and the political world. I wish it was more but it's not, I'm sorry," Graham said on CBS' "Face the Nation."

McCain's effort to reach the base with the help of President Bush has also undergone some changes. Fundraisers were going to be at public sites, but they've been switched to private homes. The White House and McCain's camp said they changed the locations because McCain prefers private fundraisers.

Others are speculating that maybe Bush's low approval ratings -- in the low 30s -- is keeping the doors closed. The Phoenix Business Journal reported Sunday that Tuesday's event was moved from the Phoenix Convention Center because people weren't buying enough tickets and the parties involved were worried about anti-war protesters.

FOX News' Caroline Shively contributed to this report.