Joe Biden will need more than a win in November and a Democratic takeover of the Senate if he wants to rival President Donald Trump when it comes to shaping the makeup of the federal courts.

He might also need lots of judges to retire.

While plenty of attention has been paid to possible openings on the Supreme Court, only a tiny fraction of legal cases ever make it to the highest court in the land. And there are no vacancies on the nation’s powerful federal appeals courts.

“He has no opportunity when he first comes in to fill any appellate vacancies because there won’t be any,” said Carl Tobias, a law professor at the University of Richmond School of Law who researches federal judicial selection.

No president going back at least as far as Ronald Reagan has been inaugurated without any spots to fill on federal appeals courts.

When Trump took office, 17 such vacancies existed, largely thanks to the fact that the GOP-controlled Senate under Majority Leader Mitch McConnell stonewalled nominations made by former President Barack Obama.

Over the nearly four years of Trump’s first term, the Senate has confirmed more than 50 of his appointees to appeals courts. Those appointees now make up more than 1 in every 4 judges on the federal appellate bench. The administration’s focus on confirming appeals court judges, even at the expense of district court judges and other priorities, was “ruthless, mercenary and single-minded,” Tobias said.

While appeals court judges don’t draw the same amount of scrutiny as Supreme Court justices, they can wield a similar amount of influence in the regions over which they preside.

Appeals courts hear about 50,000 cases per year, compared with generally about 100 for the Supreme Court. In thousands of cases each year, appellate judges have the final say.

Appellate judges have stepped in to stop presidential policies from going into effect nationwide. They often shape the law in huge swaths of the country on high-profile issues including gun rights and abortion.

A spokesperson for the Biden campaign said in a statement that the former vice president would appoint judges who are committed to the rule of law and respect precedents like Brown v. Board of Education and Roe v. Wade. Biden has previously committed to naming a Black woman to the Supreme Court.

Despite the jam-packed courts of appeals, progressives are optimistic about Biden’s potential to influence the court system via appointments.

The hope hinges on the prospect of new legislation that could expand the size of the federal bench.

Work on such an expansion is already underway.

Unlike calls to expand the Supreme Court, which the left has largely championed, both Republicans and Democrats have pressed for an increase in the size of the lower courts.

In July, the bipartisan leaders of the Senate Judiciary Committee voiced support for a measure that would create 70 new federal judgeships, including five appeals court judgeships, in line with recommendations from the Judicial Conference, the policymaking arm of the federal court system.

“Expanding the lower courts has been something that has been done routinely and on a nonpartisan basis throughout the 1900s, but over the last 30 years that has hit a wall,” said Chris Kang, chief counsel of Demand Justice, a progressive advocacy group focused on the courts.

Much of the focus on the left remains on the potential for the Supreme Court.

Elizabeth Wydra, president of progressive think tank the Constitutional Accountability Center, acknowledged that Biden, if he wins, would not come to office with the same vacancy advantage that Trump did. 

But she said that Biden would have an “extraordinary opportunity,” noting that the “Supreme Court takes the most important cases, the cases that affect the nation and that affect our most fundamental rights.” 

There are no vacancies on the Supreme Court, but the two eldest members of the panel, Justices Ruth Bader Ginsburg and Stephen Breyer, are both in their 80s. Ginsburg has suffered through a number of cancer scares in recent months, fueling speculation about an impending retirement.

The court currently has a 5-4 majority of Republican-appointed justices, including Trump’s two picks, Justices Neil Gorsuch and Brett Kavanaugh.

Possibly as a result of the court’s composition, and the fact that the two eldest justices are both liberals, Democrats are more energized about the prospect of Supreme Court vacancies than they have been in recent cycles.

While conservative voters were more likely than liberals to list the Supreme Court an important issue in 2016, the script has flipped heading into 2020.

In a survey published in August by the Pew Research Center, 66% of Biden supporters said that Supreme Court appointments were a very important issue to them, compared with 61% of Trump supporters.