WASHINGTON — The nation’s capital is preparing for a massive rally in support of gun control, one that organizers hope will prove that the country has reached an emotional tipping point on gun violence, with teenagers seizing the initiative and leading the demand for change.

Organizers are hoping to draw 500,000 protesters to bolster claims that the nation is ready to enact sweeping changes to its gun control laws. More than 800 other concurrent marches are planned in cities across America and dozens of locations overseas.

The students have tapped into a powerful current of pro-gun control sentiment that has been building for years. They have also partnered with well-funded groups such as Everytown for Gun Safety, the gun control advocacy group founded by former New York mayor and billionaire Michael Bloomberg.

“To me, it feels like this is THE moment when it’s all going to change,” said Anne Tumlinson, who will be hosting about a half dozen high school demonstrators from Jacksonville in her Washington home. A grassroots campaign among Washington residents resulted in more than 1,500 Washingtonians offering their homes to demonstrators.