Clinton has not yet announced that she's running for president in 2016, but yesterday's signing had many of the trappings of a political rally.
Attendees wore stickers that read: "I'm ready for Hillary," bags were checked, the Secret Service was in place and volunteers stood in front of Clinton's tour bus asking visitors to put their signatures on a sign-up sheet to show their support for Clinton "if" she runs in 2016.
For many who attended the signing, like Adam Beck, 26, of Philadelphia, there is no "if."
"When you look at any of the available evidence, there's a pretty strong case to be made that she will be the next president," Beck said. "I think she's going to be a very difficult candidate to beat."
Clinton arrived a half-hour late to the signing. She apologized, saying that a plane had crashed at the airport she left from earlier that morning.
According to reports, that airport was the Westchester County Airport in New York, and killed on board was Richard Rockefeller, the great-grandson of Standard Oil tycoon John D. Rockefeller.
First in line in Philadelphia to get his book signed by Clinton was Dylan Hewitt, who arrived at the library at 5:30 a.m. yesterday - six hours before the signing - to score his prime spot.
Hewitt, 22, a native of Glens Falls, N.Y., and a student at the University of Pennsylvania's Fels Institute of Government, said Clinton was his "role model."
"I told her because of her service, I too can crack whatever ceilings are above my head," he said.
About five minutes into the signing, Mayor Nutter cut in line to greet Clinton. The two shared a brief conversation and laugh before he went to the sidelines, where he spoke with Huma Abedin, Clinton's long-time aide and wife of former U.S. Rep. Anthony Weiner, of New York. Council President Darrell Clarke was also on hand to greet Clinton and her staff.
Back in line - way back in line - Jamie Mallon, 54, of Kennett Square, also hoped his T-shirt would make an impression on Clinton. The shirt had a portrait of Shakespeare on the front and a tongue-in-cheek quote below that read "This sh-- writes itself."
"This may sound funny, but she's got a tough day and if I give her a little smile, that's a good thing, right?" he said of the shirt.
Mallon said he wanted to thank Clinton, welcome her to Philadelphia and tell her one more thing when he met her.
"Whiz wit!" he said. "Don't order Swiss cheese!"
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