briefly joined House Democrats for their sit-in Wednesday demanding legislative action on gun control.

The presidential candidate, who has yet to concede to Hillary Clinton Hillary Diane Rodham ClintonJeff Flake: Republicans 'should hold the same position' on SCOTUS vacancy as 2016 Momentum growing among Republicans for Supreme Court vote before Election Day Warning signs flash for Lindsey Graham in South Carolina MORE in the Democratic primary, took to the House floor late Wednesday afternoon, joining a handful of senators who walked across the Capitol to express their solidarity with the protest.

Sanders waved as his House colleagues met him with strong applause, and he left shortly after.

Change only happens when people come together to say the status quo is unacceptable. We stand with you @HouseDemocrats. #NoBillNoBreak — Bernie Sanders (@SenSanders) June 22, 2016

Proud to stand with my colleagues to demand action. #NoBillNoBreak https://t.co/aARh2tppCk — Bernie Sanders (@SenSanders) June 22, 2016

Clinton didn't attend the protest, though she met with House Democrats earlier on Wednesday.

The Vermont senator has walked a fine line on gun control throughout his political career.

As a member of the House, Sanders voted against the Brady Bill, the landmark bill on background checks passed in the wake of the attempted assassination of President Ronald Reagan. Clinton and other Democrats used that vote to criticize him during his presidential campaign for not being a lifetime supporter of gun control.

He also tangled with Clinton over a vote he cast in favor of exempting gun manufacturers from civil liability in certain lawsuits, but Sanders has since backed a measure to remove that immunity.

Melanie Zanona contributed