Back in September, well before the death of Supreme Court Justice Antonin Scalia, I wrote a TPM Café article in which I called the future composition of the Supreme Court the most important civil rights cause of our time. “It is more important than racial justice, marriage equality, voting rights, money in politics, abortion rights, gun rights, or managing climate change. It matters more because the ability to move forward in these other civil rights struggles depends first and foremost upon control of the Court.” When I wrote those words, I feared that those on the left would not see these stakes, but now that Justice Scalia’s death has brought them into sharp relief, the next question is: What to do next? And the answer is the same as in all struggles for civil rights: popular protests and peaceful demonstrations.

Contrary to the hopes of some, there is no court that’s going to force the Senate to hold a hearing or a vote for a Supreme Court nominee of President Obama. Let the pundits and scholars debate the historical precedents over how nominees have been treated in the past, and whether Democrats or Republicans are more to blame over the poor treatment of judicial nominees in the Senate. In the end, as I argued last month, whether or not President Obama is successful in getting a nomination turns on political hardball not precedent. It will be only pressure on the Senate, and particularly on Republican Senators up for reelection in blue states, that can get the Republican Senate to move on an Obama presidential nomination.

That means demonstrations and rallies not only in Washington, D.C., but in front of the offices and at the campaign events of the most vulnerable Republican Senators: Mark Kirk (R-IL), Ron Johnson (R-WI), Kelly Ayotte (R-NH), Pat Toomey (R-PA) and Rob Portman (R-OH). Political ads on television and radio about the nomination may help, but they stand to be lost in the general election chatter. Showing that thousands of people care about this issue and are willing to go to the streets will show enthusiasm over this issue and Senators will pay a political price for denying even a hearing to the nominee of a president who was elected twice by the American people. When Senate majority leader Mitch McConnell feels that he could lose is Senate majority over this issue, we will become more likely to budge on it.

Writing recently in the Washington Post, Judge Richard Posner of the United States Court of Appeals for the Seventh Circuit explained the real significance of the Republican Senate’s obstruction over the nomination: “the significance of the Senate’s action lies in reminding us that the Supreme Court is not an ordinary court but a political court, or more precisely a politicized court, which is to say a court strongly influenced in making its decisions by the political beliefs of the judges.” Judge Posner, an appointee of Republican president Ronald Reagan, recognizes that on the issues most important to the American people, Supreme Court Justices are not “interpreting” law in a vacuum but making law in line with their political and ideological preferences.

All the Senators understand this: a 5-4 conservative Supreme Court will be much less likely than a liberal one to uphold the right of access to abortion, allow for climate change regulations and reasonable restrictions on firearms, overturn Citizens United, and protect minority voting rights.

Why would Republicans give in and hold a hearing which will lead to a Court majority they dislike? They will do so reluctantly, and only when they hear the voice of the people loud and clear, either during this election season, or, if not, at the ballot box on Election Day.

And this brings us to the final reason why an Obama nominee to the Supreme Court might get not only a hearing and a vote, but also a seat on the Court: the prospect of a President Hillary Clinton and a Democratic Senate means that whatever nominees might come next will present an even worse deal for McConnell & Co. If the politics go right, the Republican Senate will grab an Obama nominee rather than roll the dice on the next President.

Whether or not any of this happens or we have a vacant seat for some time depends upon people are willing to put their money where their mouth is, by peacefully taking to the streets to assure a new, progressive Supreme Court is on the way.