The Senate Rules Committee deadlocked on Democrats’ sweeping voting rights, campaign finance and ethics bill (S. 1) in a markup Tuesday, previewing the firestorm ahead if Senate Majority Leader Chuck Schumer (D-NY) brings it to the floor this summer as promised.

The For the People Act, which passed the House in March on a party-line vote, is congressional Democrats’ top legislative priority. Key provisions of the bill include expanding automatic voter registration and same-day registration; strengthening voting by mail, early voting and ballot access; combating voter intimidation and suppression; protecting elections from foreign interference; fixing partisan redistricting; and forcing disclosure of “dark money” donations to political groups.

The 9-9 Rules Committee vote this week came after a nine-hour hearing during which nearly 180 amendments were filed to the bill. Senate Minority Leader Mitch McConnell (R-KY) has said defeating the bill is his top priority in this session and has repeatedly accused Democrats of trying to “rewrite the rules of our system.”

With the Senate evenly divided, Republicans are expected to block the bill using a filibuster. Democrats are trying to reach consensus on whether to attempt to eliminate or significantly alter the Senate’s filibuster rules – which set a 60-vote threshold to overcome objections – to pass the legislation before the 2022 elections.

In her opening statement during Tuesday’s markup, Rules Committee Chair Amy Klobuchar (D-MN) referenced more than 300 bills introduced in state legislatures across the country that she said would suppress the vote and have wide-ranging implications for future elections.

“At a time when the right to vote is under attack and special interests and dark money are drowning out the voices of the American people, we need to take action,” Klobuchar said. “At its core, the For the People Act is about three simple ideas: making voting easier, getting big money out of politics, and strengthening ethics rules. These are not radical proposals. These are ideas that nearly everyone in this country agrees with.”