Mayor Michael Bloomberg kicked off today's events, which featured appearances by First Lady Laura Bush and New York Senator Hillary Clinton.

The event has brought together more than 600 leaders from around the country, in an effort to promote programs like AmeriCorps and the Peace Corps.

Speaking before the crowd today, Utah Senator Orrin Hatch said today that he and Democratic Senator Ted Kennedy are introducing a bill that would pump billions of dollars into initiatives aimed at getting more people to volunteer.

"We are, with this bill, ramping up efforts to tap the power of our nation's greatest asset – our people, to take on some of our biggest challenges" said the Republican senator. "These challenges include improving student engagement, achievement, and. of course, graduation in our schools."

Both Barack Obama and John McCain spoke at the event last night, appearing separately in a live, nearly two-hour televised forum from the school. The presidential candidates encouraged young people to serve the nation, with McCain talking up the armed services, while Obama pushed for more incentives to get students to serve their communities.

The event also took on a political tone, when both candidates were asked about community organizers. It's a post Obama has held, but also something Republicans have hammered him on, questioning the validity of the position.

"Of course I respect community organizers," said McCain. "Of course I respect people who serve their community. And Senator Obama's record there is outstanding. And so, I praise anyone who serves this nation in capacities that frankly could have been more financially rewarding to individuals rather than doing what they did."

"When I think about the choice I made – as a 23-, 24-year-old, to spend three years working with churches to help people help themselves, no insult to the president of this fine institution, it was the best education I ever had," recalled the Illinois senator.

The organization is bringing about a "Day of Action" on September 27, when more than 2,200 events are planned across the country.