Favorable rulings on the Trump administration's executive orders have been few and far between in the federal courts - evoking accusations of judicial overreach from the president as well as a recent threat to break up a liberal-leaning circuit.
But with more than 100 federal judicial vacancies, President Trump has the chance to close the gap in the number of liberal-leaning judges and conservative-leaning judges who hear cases like those challenging his executive orders.
To understand the potential benefit to the president of reshaping the courts, one need look no further than the litany of lawsuits challenging a pair of orders that would have temporarily barred refugee resettlement and travel to the U.S. by foreign nationals from six Muslim-majority countries.
Of 28 lawsuits challenging the legality of either the first or revised version of Mr. Trump's travel ban, 18 of the U.S. District Court judges assigned to hear the cases were nominated by Democratic presidents. President Obama alone nominated 15 of the presiding district judges - more than all the Republican-nominated district judges who have presided over travel ban hearings combined.
Republican-appointed judges will also be outnumbered when the Trump administration's appeal of one travel ban challenge heads to the full 4th U.S. Circuit Court of Appeals on Monday.
Of course, a judge having been appointed by a Republican president doesn't mean he will rule in the interests of a Republican administration. Case in point: James Robart, the District Court judge in Seattle who issued the injunction that blocked the Trump administration from enforcing its first travel ban order anywhere in the United States was a George W. Bush appointee.
But of those judges who have issued rulings in the cases favorable to the administration, there's one notable distinction, said Dan Goldberg, legal counsel at Alliance for Justice.
"The travel ban case is very telling in that you had both at the District Court and appellate level the overwhelming consensus of judges say that the president acted unconstitutionally and denied critical rights to individuals," Mr. Goldberg said. "The few examples of judges taking the contrary view have all been conservative Republican-appointed judges."
U.S. District Judge Anthony Trenga, appointed by Mr. Bush, declined to issue a temporary restraining order blocking the second version of the travel ban in one case brought in Virginia. He ruled instead that plaintiffs in the case were not able to establish a likelihood that they would succeed on the merits of the case or that there would be a public interest in putting off enforcement of the executive order.
And in Massachusetts, U.S. District Judge Nathaniel Gorton - who was appointed by George H.W. Bush - refused to extend a restraining order against Mr. Trump's first executive order.
Conversely, a three-judge panel from the 9th U.S. Circuit Court of Appeals - consisting of two Democratic and one Republican appointee - ruled the first version of the order was likely illegal and upheld Judge Robart's earlier restraining order. But when the 9th Circuit later declined an en banc hearing to reconsider the panel's earlier decision against the Trump administration, it was five Republican-appointed judges who filed a dissent, arguing the panel had erred in upholding the restraining order preventing enforcement of the first travel ban.
Rulings by two Obama-appointed federal judges in Maryland and Hawaii have thus far helped prevented the Trump administration's second version of the order from going into effect. Both have been appealed and are scheduled to be argued before the 4th Circuit on Monday and the 9th Circuit on May 15.
With the revised executive order blocked for now, many of the more than two dozen legal challenges filed over the travel ban have been placed in a holding pattern, leaving it up to guesswork as to how judges in those cases might have ruled, said Margo Schlanger, a professor at the University of Michigan Law School who has been tracking lawsuits brought against the Trump administration through the school's Civil Rights Litigation Clearinghouse.
But so far no Democrat-appointed District Court judges have issued rulings considered favorable to the Trump administration.
According to a New York Times report, Mr. Trump was set to announce 10 nominees to lower federal courts on Monday.
The president's ability to fill federal judicial vacancies with conservative judges could help him down the road if other policies are challenged in court, Ms. Schlanger said.
"The Democrat-appointed judges tend to be more progressive and the Republican-appointed judges tend to be less so. I expect that will correlate some but so far not as much as you would think," she said, referring to the mixed results from Republican-appointed judges. "When President Trump names a bunch of district judges it will make a difference in a lot of cases."
Thanks to the 331 federal judgeship appointments made by Mr. Obama during his eight-year term, it's unsurprising Democrat-appointed judges would have been assigned more frequently to travel ban cases, said Russell Wheeler, a fellow at the Brookings Institution's Governance Studies Program.
When Mr. Trump was sworn into office in January, Democratic appointees held 51 percent of the 673 District Court judgeships, while Republican appointees held 34 percent of the judgeships, Mr. Wheeler said. Fourteen percent of judgeships, or 96 seats, were vacant. That's a dramatic change from when Mr. Obama took office - there were only 39 vacancies and Republican-appointed judges held almost 60 percent of the posts, or 371 seats, Mr. Wheeler said.
Even though Mr. Trump has previously acknowledged his potential to reshape the courts, promising to appoint pro-life and pro-gun judges, legal experts say the president will likely have to compromise on some fronts in order in order to get nominees confirmed by the Senate.
The Senate Judiciary Committee's "blue slip" policy gives senators a chance to weigh in and potentially block a judicial nominee from their state - a likely scenario in states with Democratic senators. Sen. Chuck Grassley, the chairman of the committee, has said he intends to follow the blue slip tradition for Mr. Trump's nominees.
"The president doesn't have a completely free hand in making those choices where senators are blocking them," said Carrie Severino, chief counsel and policy director at the Judicial Crisis Network, a conservative legal group.
Under Mr. Obama, nominations took significantly longer to be submitted in states with Republican senators, Mr. Wheeler said, highlighting the degree to which lawmakers were bargaining over appointments.
Lawmakers and legal observers will likely both be looking for signs that nominees will be able to demonstrate an ability to be an independent check on the executive branch, Mr. Goldberg said.
"It could be deeply troubling if he's going to insist on nominating extreme jurists who are ideologues as opposed to mainstream jurists," Mr. Goldberg said.
But even as the president has signaled time and again his frustration over unfavorable rulings - lashing out and accusing the courts of judicial overreach as well as deriding the opinion of a "so-called judge" as "ridiculous" - he has thus far put forth only two nominations.
The Supreme Court nominee, Judge Neil M. Gorsuch, was quickly approved by the Senate and the nomination of Judge Amul R. Thapar for the 6th U.S. Circuit Court of Appeals is still under consideration.
While much of the attention surrounding Mr. Trump's judicial nominations has centered on Judge Gorsuch and speculation over who he will pick to fill the 20 appeals court vacancies, legal analysts say his choices for the 101 open District Court seats could broadly affect everyday Americans who come to the courts seeking legal remedies.
"At the trial level, you get the judge that you get," Ms. Severino said. "So you can have a situation where there is only one judge behaving in a political way. But if that is your judge, that is what you have to face for that case."
Last year, 274,552 civil cases and 79,787 criminal cases were filed in district courts.
"Even if what he does is appoint more moderate conservative judges, expect it to mean something in the cases in which they sit," Ms. Schlanger said.