Protesters for and against abortion rallied March 2 outside the Supreme Court as the justices heard argument in Whole Woman’s Health v. Hellerstedt.

Assuming a Neil Gorsuch-like nominee is confirmed to the U.S. Supreme Court, the court’s coalition of five solid conservatives might be capable of rolling back Roe v. Wade, cutting back rights of the LGBT community and eliminating affirmative action policies. But that doesn’t mean progressives are powerless against such rollbacks.

First, it becomes necessary to strengthen the court system in every state. Second, Democrats must prepare a court packing law—increasing the number of justices on the Supreme Court—to pass should they reclaim the White House and control of Congress in the 2020 elections.

The Supreme Court may have the final say on interpreting the U.S. Constitution, but the highest courts in each state individually have the final word on what their state constitutions mean. Each of the state constitutions contain wording similar to that of the federal instrument—every citizen of the state is promised due process of law and the equal protection of the laws.

State courts usually interpret their constitutions in line with what the U.S. Supreme Court says about the federal Constitution. But they are not required to do so. For example, New York courts have held that the exclusionary rule applies in parole revocation hearings under the New York Constitution, even after the U.S. Supreme Court held that the federal Constitution does not require its application in such hearings. The Wisconsin Supreme Court recently held that any evidence secured as a result of the violation of the Miranda rule must be suppressed, going far beyond any U.S. Supreme Court decision on that point.

The Iowa Supreme Court just held that under the Iowa Constitution, an Iowa law that required women to wait three days before they can get an abortion is invalid since it places an undue burden on a woman’s right to have an abortion. The court held that it “jealously guard[s]” its “right and duty to differ from the [United States] Supreme Court in appropriate cases, when construing analogous provisions of the Iowa Constitution.” There is no appeal from that ruling since the Iowa Supreme Court has the final say on what the Iowa constitution means.

So, assuming the new conservative Supreme Court decides to overrule Roe, in theory the supreme courts of the other 50 states could conclude that the rule established in Roe still applied under their constitutions. The judges of the highest courts of each state are chosen in different ways. For the most part, in 38 states, they are elected, and sometimes they are chosen by the governor based on recommendations by the legislature or special selection committees. But progressives in each state must make a special effort to elect liberal judges and to elect Democratic governors and legislators who will move their court system in the right direction, regardless of what the Supreme Court does.

The other way to prevent the inevitable overruling of Roe by a new conservative Supreme Court is by expanding the number of justices from nine to 11 or 13. The constitution says nothing about how many justices must sit on the Supreme Court. Congress was required to establish the court, but there were no requirements on its size. The first Supreme Court had six members. Congress increased the size of the court to seven in 1807 and to nine in 1837. It was briefly increased to 10 after the Civil War but returned to nine in 1869, where it has stayed ever since.

President Franklin Roosevelt tried to “pack the court” in 1937 after the very conservative court in the early 1930s had struck down a number of important New Deal laws. After his overwhelming election victory in 1937, Roosevelt believed he had the mandate to do something about the court, which was standing in the way of his New Deal program. He proposed adding one justice for every justice who reached 70 years of age. That would have allowed him to appoint five new justices. But one of the conservative justices, Owen Roberts (no relation of the current chief justice), switched his vote in an important case dealing with the National Labor Relations Act, upholding the law. That change in voting pattern convinced Congress that packing the court was no longer necessary. It was a “switch in time that saved nine.”

So, at the very worst, a case dealing with this kind of precedent may not get to Trump’s new Supreme Court until 2021. By that time, a new Democratic Congress may ride a blue wave to increasing the members of the court, at which point Roe is likely upheld.

As with almost all political problems, the answer is better politics. We must get more people to vote. We must tell them why it is in their interest to do so. We must energize the voting base that often ignores the voting box. It is hard work to convince people to vote and to vote for your candidate. But that is the way to solve most problems including difficult legal problems.

Leon Friedman is a professor of constitutional law at Maurice A. Deane School of Law at Hofstra University. He is the editor of, and contributor to, “The Justices of the United States Supreme Court: Their Lives and Major Opinions.”