Sen. Barack Obama, D-Ill., and his team may have passed their first real presidential test -- they can keep a secret.
Obama and his White House rival Sen. John McCain, R-Ariz., are both enjoying the anticipation of their looming choices for vice presidential running mates.
McCain's camp has indicated that he is still mulling his choices, but Obama has a real secret to keep.
The presumptive Democratic nominee has made his choice, but as of Monday night he hadn't even shared that information with the person he selected.
And it's not clear whether the winner of the Democratic veepstakes has yet to be notified.
Summer's Hottest Hit? Vice Presidential Clue
Intent on finding clues, veep watchers have staked out the homes of those believed to be on Obama's short list and are monitoring every word, schedule and grooming change.
One possible slip may be an indication that Obama has finally ruled out New York's Sen. Hillary Clinton and two-term Kansas Gov. Kathleen Sebelius.
Obama usually uses the phrase "he or she" when talking about a future running mate, but in a speech in Raleigh, N.C., Tuesday night, he dropped the "she."
"My vice president also, by the way, will be a member of the executive branch. He won't be one of these fourth branches of government where he thinks he's above the law," Obama said.
Other clues are more circumstantial.
Obama will be campaigning in Virginia Thursday with Gov. Tim Kaine, one of three believed to still be on Obama's list.
It's expected Obama will make his vice presidential announcement public by the end of this week if for no other reason that simple necessity: the Democrats' nominating convention opens in Denver Monday.
Unless Kaine's grin was a hint, the governor gave no clue if has finally been told by Obama that he is -- or isn't -- the one.
"I won't talk about my conversations, but we're thrilled he'll be in Virginia," Kaine said Tuesday.
Vice Presidential Speculation Reaches Silly Season
Nothing is beyond scrutiny as the summer heat sizzles and political reporters angle to break one of the few anticipated big moments in a presidential campaign.
When Susan Bayh, wife of Indiana Sen. Evan Bayh, got her hair and nails done this week and told neighbors that she had to "prepare for a media pack," was it another clue or just coincidence?
Sen. Joe Biden, D-Del., may have given up something Tuesday when he told reporters while driving slowly past them, "It isn't me," but since then he's refused to elaborate.
This morning he cruised past the press pack at the end of his driveway with his windows rolled up.
He returned a short time later and rolled his window down long enough to hand over a brew box of coffee and a dozen bagels. "Nice talking to you," was all he said.
Select Group Keep Obama's Confidence
The only people who know for sure who the choice is could fit into a midsize car.
Besides Obama, there are two people who led the vetting process, Caroline Kennedy and former Justice Department official Eric Holder; top campaign aides David Axelrod and David Plouffe, and Obama's wife Michelle were also involved.
Mike Feldman, former top aide to one time Democratic presidential candidate Al Gore, said there is a good reason for Obama to protect his secret.
"They have very few moments where they can completely control: the nomination and announcing -- this is one of those," Feldman said.
What is known is that when Obama is ready to make his selection public, staff at his campaign headquarters will send out the word by e-mail and text message to thousands of supporters as well as the media.
And Obama and his running mate will kick off a swing through battleground states with a rally Saturday in Springfield, Ill., the same spot where Obama announced that he was a candidate for president 18 months ago.
Unknown Running Mates Find Spotlight
The political scrutiny has unearthed interesting details about the three Democrats waiting in the wings.
For instance, Kaine plays the harmonica. And despite the fact that Kaine and Obama have lived as far apart as possible and still be in America -- Hawaii and Virginia -- they both have origins in the middle of the country.
"My mom and my grandparents and his mother and grandparents both spent formative time in El Dorado, Kan.," Kaine has said.
If the ticket is Obama-Kaine, it would feature four Harvard Law grads, since Obama and Kaine, as well as their wives, are all Harvard Law alumni.
Obama and Bayh also have a few things in common.
Obama gave the convention keynote address in 2004, and Bayh gave the keynote in 1996. Bayh's father, Sen. Birch Bayh, D-Ind., made a presidential bid in 1976 under the slogan "Yes, we can." While it didn't work for Bayh's father, he's hoping it works for an Obama-Bayh ticket.
The Obamas have two children, as do the Bayhs, although the Bayh kids are twins.
Also, Bayh likes to run marathons, which is a good thing because this is the third time he's been in the running for the VP slot since 2000.
Biden doesn't have such striking things in common with Obama.
Obama likes basketball, while Biden is a weight lifter. But Biden, like Obama, has a history of overcoming problems. Once a stutterer, Biden is known these days as a nonstop yakker.
Biden has also had to overcome tragedy. His first wife and young daughter died in a car accident before he first took office more than 30 years ago.
"The only way you deal with those things, I think, you just got to focus on what's left, what you have," the Senate veteran said of the tragedy in an interview with ABC News anchor Charles Gibson.
While the consummate Washington insider, he's never lived a day in D.C., commuting each day via Amtrak from his home in Delaware.
Conservative Republicans Surveyed on 'Pro-Choice' Candidate
The Republicans can afford to take a little more time with their veep decision, since the GOP convention begins Monday, Sept. 1, a week after the Democrats.
McCain reportedly intends to announce his choice Friday, Aug. 29, the day after the Democrats end their convention.
McCain supporters are calling around to top party donors and Republican delegates asking how they would feel if McCain picked a running mate who supports abortion rights, like former Pennsylvania governor and Homeland Security chief Tom Ridge.
The reaction from conservatives in the party has not been positive.