The outpouring of support in Tucson tonight was evident as thousands waited in line, some sleeping on the ground overnight, to enter the McKale Memorial Center this afternoon. The university set up an area to handle the overflow of students and other attendees who camped out on the sidewalk under the desert sun.
The hour-long memorial this evening was thrown together quickly as a way to gather and mourn. A Native American blessing opened the program followed by a welcome speech from University of Arizona President Robert N. Shelton and, of course, the playing of the National Anthem.
Arizona Gov. Jan Brewer and two student speakers from the university, student body president Emily Fritze and David Hernandez, also made remarks.
Napolitano, who formerly was Arizona's governor, and Attorney General Eric Holder both spoke. Napolitano quoted from the book of Isaiah, and Holder read from the second letter of Paul to the Corinthians.
Supreme Court Justice Anthony Kennedy represented the judicial branch in the audience, and House Minority Leader Nancy Pelosi, D-Calif., Reps. Paul Gosar, Jeff Flake, Trent Franks, Ben Quayle and Dave Schweikert represented the legislative.
The memorial service concluded with the signing of the hymn "Come Thou Fount."
The feeling in Tucson was a bit divided about what the president would and should say. All agreed the president's message should be one of unity and healing focused on the victims of the tragedy.
"I believe that the president should maybe focus more on the families and the healing aspect of what happened -- the tragedy," said Lisa Engelberg, a 30-year resident of Tucson.
Engelberg added that as the community heals, there should not be politics in the president's message tonight.
"I think today might need to be about those who were the victims of the shootings and their families and not so much the politics," she said.
Seth Landy, a resident of Tucson, said the community just needed some "guiding words" -- but confessed that at some point politics is going to have to be part of the discussion.
"I do think it's important that the president talk about the victims and the families, you know, but eventually the politics are going to have to come into it," Landy said. "I think that gun control needs to come up tonight, I really do, you know, because so many people are talking about this."
Rishelle Baines, a student at the University of Arizona, said the politics of the shooting is a part of the president's message -- but it shouldn't be the emphasis.
"I just think we have to step aside and really just worry about everybody healing and coming together," Baines said. "Yes, politics is a part of it but I really think first we just have to be human and think about everybody healing. ... That's the biggest thing."
Mark Speers of Tucson, among the many who waited in line for the speech, said Obama's appearance tonight was -- in essence -- almost like the moment of silence he observed on the South Lawn at the White House on Thursday.
"It wasn't about him saying anything at that moment," Speers said. "I really feel that he would do just that. It's about the cause of what just happened and reaching out to people to kind of heal some of that."
The politics of the tragedy will be more appropriate to discuss on another day, Speers said.
"A heated debate seems to already be going on," Speers said, "so I think it's important that today happens for what it is, and I think tomorrow is another day to present that."
ABC News' Dan Harris and Michael S. James contributed to this report.