After the Supreme Court’s decision in the Citizens United case, we all learned a new political term: “super PAC.” Now, after the court’s decision in McCutcheon v. FCC on April 2, get ready for another one: “Joint Party Committee.”

Why? Because such a committee makes it easy for someone with a lot of money to influence our elections—with just one check.

The good news is that the momentum for a constitutional amendment is growing

Here’s what’s going on. The court left in place the limit of $5,200 that you can give directly to a single candidate in a single election cycle They also left in place the limits of $5,000 you can give to a political action committee, $10,000 that you can give to a state or local political party, and $32,400 you can give to a national party.

What the court lifted was the total amount you can give to all federal candidates, political parties, and committees. Before the McCutcheon decision, the limit was $123,200. Now you can give as much as you want.

Of course, for most of us, that $123,200 limit was not really a limit. We don’t have that much to give in the first place. So who does this benefit? Only the very rich. They get more power to influence elections. And in doing so they may override the concerns of the vast majority of our nation’s people.

The arrival of “joint party committees”

You might ask whether lifting the aggregate limit is really a problem, since the limits for direct contributions to candidates and parties are still in place. Why shouldn’t someone be able to give to as many candidates and political parties as they want?

According to a detailed report from the nonprofit consumer advocacy group Public Citizen, here’s what’s likely to happen. A politician, say John Boehner or Nancy Pelosi, forms a joint party committee. You—with your spare millions—say “Great! I want to give to every single candidate running for federal office in the party, and all the political parties and committees too.”

So you give your big check to the joint party committee to spread around. Your money can go to all 435 candidates for the House; 34 candidates for the Senate; plus all the party committees. Some of those candidates’ seats are so secure that they don’t need the money, so they return it to the party to spend as it wants. The party, of course, will use it to hammer opposition candidates in sharply contested races.

In his dissenting opinion, Justice Stephen Breyer noted that the formation of joint party committees may well happen and confound the intent of the limits. But Justice John Roberts, writing for the majority, said he found that outcome unlikely.

Just as the Citizens United decision blew a hole in the limits a person or corporation can spend on so-called “outside groups,” McCutcheon blows a hole in the amounts that individuals can contribute directly to candidates.

Given the power of the Supreme Court, there are only two ways to fix the Citizens United and McCutcheon decisions: The first is to get justices on the Supreme Court who don’t think allowing the rich to spend vast sums on elections is simply a form of free speech, and who are ready to reverse these decisions. Given their dissents, we likely already have four such justices. The second is to pass a constitutional amendment to overrule these two decisions.

Momentum builds for a constitutional amendment

The good news is that the momentum for a constitutional amendment is growing. Already, 16 states and more than 500 towns and cities have passed referendums recommending an amendment to overturn the effects of the Citizens United decision. More states are on the way. There are 14 resolutions in the U.S. Congress recommending various forms of a constitutional amendment to curtail the money flooding into our politics. And just one day after the McCutcheon decision, the ruling was already bringing more co-sponsors to those resolutions.

Just how long it takes to overturn these terrible decisions will depend on how many of us act now.

On April 2, I marched in a rally against the McCutcheon decision on Bainbridge Island, carrying a petition for Washington state’s own initiative in support of a constitutional amendment. The folks I met on the street were eager to sign.

“People across the country are angry that five corporatists on the Supreme Court could overturn the basic premise of American democracy,” was how John Bonifaz of the clean elections group Free Speech for People put it.

This is a great time to join the movement. I personally believe we will overturn these terrible decisions. Just how long that takes will depend on how many of us act now.