More than 3,600 people pledged to participate in the sit-ins, expected to continue throughout this week, according to Democracy Spring, the group organizing the protests.
"Almost every American agrees our democracy is seriously out of whack — that our elections and government are dominated by wealthy special interests. And yet Congress is doing nothing. So today we say no more,” lead organizer Kai Newkirk said in a statement.
The protesters are calling for votes on four specific bills to create a public campaign financing system; restore a provision of the Voting Rights Act struck down by the Supreme Court that requires federal approval of changes to voting procedures in certain states; modernize voter registration; and overturn the Citizens United decision that allows corporations to spend unlimited sums in elections.
Although the protesters do not have a position on President Obama’s Supreme Court nominee, they are also urging the Senate to hold hearings to shed light on Merrick Garland’s positions on campaign finance and voting rights policies.
The protests are expected to last throughout this week. The demonstrators' first sit-in on Monday began at noon, following a rally near Union Station.
The Senate is in session on Monday, while the House will not return from its spring recess until Tuesday night.
— This post was updated to 6:13 p.m.