Bernie Sanders will campaign on behalf of his one-time Democratic rival, Hillary Clinton, on Labor Day. 

The New Hampshire AFL-CIO announced that the Vermont senator would speak at its Labor Day breakfast Monday in Manchester. 

"At the breakfast, Senator Sanders will discuss the challenges facing working Americans and why we need to increase the minimum wage to $15 an hour, enact paid family medical leave, oppose the Trans-Pacific Partnership and create new jobs rebuilding our crumbling infrastructure," the group said in a statement. 

"He also will talk about why he supports Hillary Clinton for President and Governor Maggie Hassan for the U.S. Senate and discuss their shared vision of how to build an economy that works for everyone — not just those at the top."

Hassan is facing incumbent Sen. Kelly Ayotte (R) in a toss-up race as Democrats look to regain control of the Senate.