The deadly shooting spree in Colorado consumed the presidential campaign Friday, with President Barack Obama cutting his Florida trip short and challenger Mitt Romney altering his scheduled events for the day.
Sidetracking a bitter political contest with a tragedy that at least temporarily brought the candidates together in common purpose, both candidates issued statements of condolences, calling for prayer and unity in the aftermath of the overnight bloodshed at a suburban Denver movie theater.
Obama make brief remarks during a scheduled appearance in Fort Myers and canceled an appearance in Winter Park and was returning to Washington ahead of schedule.
"We may never understand what leads anyone to terrorize their fellow human beings. Such violence, such evil senselessness is beyond reason," Obama told those who had arrived at Friday morning appearance. "We do know what makes life worth living. People in Aurora loved and were loved."
In addition to altering his schedule, Obama campaign also asked affiliates to temporarily pull its advertising.
Romney, too, was to address the matter at a previously scheduled campaign event in New Hampshire. He canceled some media interviews.
Obama was notified at dawn at his hotel near West Palm Beach, Fla., by his counter-terrorism adviser, John Brennan. The White House said there was no apparent connection to terrorism.
"As we do when confronted by moments of darkness and challenge, we must now come together as one American family. All of us must have the people of Aurora in our thoughts and prayers as they confront the loss of family, friends, and neighbors," Obama said in a statement.
Romney, in his own statement, said: "We are praying for the families and loved ones of the victims during this time of deep shock and immense grief. We expect that the person responsible for this terrible crime will be quickly brought to justice."
The assault by apparently one shooter killed 12 people and injured at least 50 others in one of the deadliest mass shootings in recent U.S. history.
The enormity and horror of the incident immediately injected a new tone to the campaign, essentially demanding that both candidates for the time halt politics and attend to the nation's shock at the tragedy.
The Obama campaign rushed to pull down negative advertising on television. Vice President Joe Biden canceled a fundraiser in Texas and first lady Michelle Obama did the same for planned campaign events in Virginia.
White House spokesman Jay Carney said that Obama's "first reaction upon hearing about this was his immediate concern that the incident was over that no other people were in danger. His second reaction was what you feel as a parent," Carney said, pausing to collect himself, "as you can imagine."
Carney later added: "He mentioned to me how heavy his heart is and the pain he understands parents and loved ones must be suffering."