Tim Pawlenty, John Thune, Joe Lieberman, Rob Portman and Mike Huckabee appear to be humming the same vice presidential tune -- or reading from the same talking points -- these days

"I don't expect to be asked," they have all said recently about their vice presidential ambitions.

The quintet represents a fraction of the names bandied about as possible running mates for John McCain but they are all frequently mentioned and are among the most serious candidates.

Sure, the sentence is only six words long, and others have uttered it in relation to the vice presidency, including Alaska Sen. Lisa Murkowski on the Republican side and several Democrats. But anytime you hear several politicians use precisely the same words, it's worth wondering whether they are simply staying on a message delivered to them by someone else.

Here (with research help from Zach Beauchamp) is at least one instance of each saying what might be the magic words for a short-lister:

• Pawlenty at a Chamber of Commerce meeting June 18: "I'm honored to have my name mentioned. The fact is, I haven't been asked, and I don't expect to be asked."
• Thune on KELO television in South Dakota July 9: "I don't have, as I said before, any intentions on that job. And I don't expect to be asked."
• The same day Portman said to me: "I appreciate being on some of the lists ... I really don't think I'm going to be asked." A couple of weeks earlier he told FOX News "I don't expect to be asked."
• Huckabee told Radio Iowa July 12: "I don't expect to be asked. I really don't.   It's pretty clearly obvious that what I'm doing -- I'm not sitting around waiting on the phone to ring and right now it would really mess up a lot of things I have going."
• Lieberman in today's New York Times: "I'm not really interested, and I don't expect to be asked."
  

Former budget director/trade representative/congressman and frequent Veep mention Rob Portman says he expects that John McCain's campaign will wait as long as possible to name a running mate.

"My sense is that they are wisely waiting to see what the dynamics of the race are closer to our convention which will include knowing who Sen. Obama picks," Portman told me by phone as he traveled to a McCain event in Portsmouth, Ohio, yesterday. "I think that's smart to wait and have the best information possible."

He also said he can't handicap the field.

"I don't really know what their short list looks like or necessarily what their priorities are," he said.

Portman has been stumping for McCain across Ohio, a task that not only gives him face time with the presumed nominee but also allows him to build statewide contacts should he run for governor or senator in 2010.

He said McCain has a lot of good options and that he probably won't be the one to be number two.

"I appreciate being on some of the lists," Portman said. "I really don't think I'm going to be asked."

Portman backers note his handle on economic matters and his roots in the swing state of Ohio as plusses in the vice presidential calculus. But his ties to the Bush administration and limited reach outside his old Cincinnati district weigh against him.

Portman acknowledged that campaigning for McCain is giving him a chance to build better statewide contacts in preparation for a possible run in 2010, when Democratic Gov. Ted Strickland would be up for re-election and Republican Sen. George Voinovich is expected to retire.

Portman, who has kept his congressional fundraising committee open, acknowledged the secondary benefits of stumping for McCain should he choose to make a bid.

"It could be useful," he said. "I'm going to make a decision at the end of this year."

For now, he said, he is happy to be promoting McCain.

"I think he's the right person for this country in what is a tough time," Portman said.