Updated 01/21/13 - 11:14 a.m.
CHICAGO (CBS) -- About 600,000 people were in Washington on Monday for President Obama's second inauguration ceremony.
Special Moment For Durbin
He formally took the oath of office for his second term on Sunday. His public swearing-in took place on the steps of the U.S. Capitol on Monday.
This inauguration is special for Illinois Sen. Dick Durbin, who introduced Obama to the world political stage in 2004.
Durbin has been there for many significant political milestones for Obama, but he considers this one of the happiest days of his political life.
"Helping the president make the decision to move forward and run the first time is something I will always remember," Durbin told WBBM Newsradio Political Editor Craig Dellimore. "He's been kind enough to thank me for it from time to time."
"This re-election was critically important. It was an affirmation of what he stands for, what he is fighting for," Durbin added.
Gov. Pat Quinn, who was also in D.C. for the inauguration, said it's appropriate the event coincided with the day the nation honors Rev. Dr. Martin Luther King Jr.
Quinn: Obama 'An Inspiration To All Of Us'
The governor said Illinois was the first state in the union to recognize the need for a holiday honoring King. The civil rights leader and his family lived in Chicago briefly.
"They lived in our city, our state, for the year of 1966, and that's why I think our state recognized the need for a holiday; a day on, not a day off – a day of service honoring Dr. King," the governor said. "And then to have the president – President Barack Obama – inaugurated on that very day, in 2013, 50 years after the 'I Have A Dream' speech, I think is God's grace."
The governor said he'll be happily braving the cold on the steps of the U.S. Capitol to watch Obama's second inauguration.
"It's a proud day for the United States of America, and a proud day for Illinois," he said. "A favorite son of Illinois, President Barack Obama, will be sworn in again, as president, and he's an inspiration to all of us. And I think we ain't seen nothing yet."
Quinn said he looks forward to working with the president to see his health care initiatives fully take effect, and provide coverage for so many more people.
Durbin told CBS 2 Chief Correspondent Jay Levine that winning the second time and celebrating the inaugural is a "liberating event" for the president.
Durbin talked about how Obama was emotional after campaigning for the last time.
"There will be a difference in attitude in approach" during his second term, Durbin said.
And perhaps a different style: Obama may be more relaxed, more revealing and focused on his legacy.
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