Thousands of demonstrators rallied Saturday in Washington to demand tougher gun control laws, many describing themselves as first-time capital marchers who've had enough of gun violence.

On a cold day, a vanguard led a blocks-long procession with a big blue banner, declaring "March on Washington for Gun Control: When we stand together, we stand a chance."

The demonstrators want reinstatement of the federal ban on the sale of military-style semi-automatic rifles such as the one used in the recent Newtown, Connecticut, school shooting that left 20 children and six adults dead, plus the gunman and his mother. The protestors also want a ban on the sale of high-capacity ammunition magazines and universal background checks.

Many marchers just carried black-and-white placards bearing the names of victims of gun violence, such as Veronica Soto, a Newtown teacher who was killed in the Sandy Hook Elementary massacre.

Co-organizer Molly Smith highlighted how many demonstrators were ordinary citizens, the organization of whom was assisted by a webpage and Facebook page.

"It's been a remarkable learning experience," Smith told CNN, "the realization that we're citizens and this is an active citizenship, and being a citizen isn't just sitting around and gassing about it."

The march was the first major demonstration since the Newtown mass shooting last month, and it comes two days after Sen. Dianne Feinstein, D-California, introduced a bill that would ban some assault rifles, semi-automatic weapons and high-capacity magazines.

U.S. Education Secretary Arne Duncan told an assembly of marchers, after they reached their rallying area midway between the White House and the Capitol, that Saturday's demonstration wasn't about the Second Amendment.

"This is about gun responsibility; this is about gun safety; this is about fewer dead Americans, fewer dead children," Duncan told the crowd.

He recalled that as the former chief of Chicago Public Schools, he oversaw a system in a city where a student was killed by gun violence every two weeks.

"Far too many of our children are growing up in climates where they are scared," Duncan said. "That has to change."

He added, "This march is a starting point. It's not an ending point. We must act, we must act, we must act."

U.S. Rep. Eleanor Holmes Norton, D-District of Columbia, asked residents of Newtown, Connecticut, to make themselves known in the crowd.

'We came to stand with you and bear witness with you until we vindicate your children and those who died with them," Norton said.

She urged the assembly to press for gun reform.

The demonstrators started chanting: "Yes, we can! Yes, we can! Yes, we can!"

Without mentioning the National Rifle Association, Norton made a reference to the powerful gun lobby, saying, "It comes down to us because we are immune to their lobbying.

"Only an outraged public can end the gun violence that has enveloped our country," she added. "We the people who did not act before, we the people this time will step forward.

"And this time we will not step back."

Colin Goddard survived being shot four times during the Virginia Tech massacre in 2007, the deadliest shooting in U.S. history, one that left 33 people dead, including the gunman, who took his own life.