Ramping up its campaign to fill powerful committee seats with lawmakers dedicated to fighting for Medicare for All, a Green New Deal, and other bold and popular policies, a coalition of grassroots advocacy groups will march to the office of Nancy Pelosi (D-Calif) Thursday afternoon to make their voices heard.

"The grassroots progressive movement is flexing more power than ever before," said Waleed Shahid, a spokesman for Justice Democrats, one of the 13 groups taking part in the delivery of over 150,000 petition signatures to Pelosi's Washington, D.C. office. "Now we need to see that energy translated to the most powerful committees in Congress."

Watch the petition delivery:

Specifically, the coalition of advocacy groups—which collectively represent millions of Americans—are calling on Pelosi to appoint:

• Rep.-elect Alexandria Ocasio Cortez (D-N.Y.) to Ways and Means;
• Rep.-elect Rashida Tlaib (D-Mich.) to Appropriations;
• Rep.-elect Katie Porter (D-Calif.) to Financial Services;
• Rep. Pramila Jayapal (D-Wash.) to Ways and Means and Judiciary; and
• Rep. Ro Khanna (D-Calif.) to Ways and Means.

In exchange for the support of the Congressional Progressive Caucus (CPC) in her bid for the House Speakership, Pelosi vowed to give CPC members at least 40 percent of the seats on five key committees: Ways and Means, Energy and Commerce, Intelligence, Financial Services, and Appropriations.

The grassroots coalition's pressure campaign, which launched earlier this week, is aimed at holding Pelosi's feet to the fire and tilting the balance of committee seats away from Wall Street Democrats more interested in fighting for their donors than progressive legislation.

The groups taking part in Thursday's action are Social Security Works, CREDO Action, Democracy for America, Democratic Socialists of America, Justice Democrats, Friends of the Earth Action, Demand Progress, CPD Action, Progressive Change Campaign Committee, Progress America, Progressive Democrats of America, UltraViolet, People Demanding Action, The Zero Hour, and The Other 98%.