ROUGH CUT (NO REPORTER NARRATION) STORY: President Barack Obama, marking a poignant moment in his push to curb gun violence, awarded presidential medals posthumously on Friday to six educators killed in the Newtown school massacre, saying they gave their lives to protect "the most innocent and helpless among us." Obama bestowed the honor, which recognizes citizens who have performed "exemplary deeds" of service, on four teachers and two administrators killed in the December 14 shooting rampage at Sandy Hook Elementary School in Connecticut, a tragedy that sparked nationwide calls for tighter gun control laws. In a White House ceremony, Presidential Citizens Medals, the nation's second-highest civilian honor, were presented one-by-one to the slain women's families, many of them in tears as Obama embraced and consoled them. Twenty first-graders were also killed in the attack by a lone gunman. Obama said the educators came to school that morning with "no idea that evil was about to strike." "And when it did they could have taken shelter by themselves, they could have focused on their own safety, on their own well-being, but they didn't," he said. "They gave their lives to protect the precious children in their care and gave all they had for the most innocent and helpless among us. That's what we honor today." Obama, who has called the day of the mass shooting the worst of his presidency, is moving swiftly to try to build momentum for gun control legislation, using his otherwise policy-heavy State of the Union address on Tuesday to make an impassioned appeal. But he faces an uphill battle against a powerful pro-gun lobby and a strong U.S. tradition of hunting and gun ownership. The right to bear arms is enshrined in the Second Amendment of the U.S. Constitution. Principal Dawn Hochsprung, school psychologist Mary Sherlach and teachers Rachel D'Avino, Lauren Rousseau, Anne Marie Murphy and Victoria Soto were killed in the attack carried out by the 20-year-old gunman, Adam Lanza. Obama paid tribute to the slain educators in a ceremony that also honored a dozen other Americans in fields that included child development, gay rights, military veterans assistance, immigrant outreach and helping disabled women. They were selected from among nearly 6,000 nominations.