The Senate has confirmed Kenneth Lee to the 9th U.S. Circuit Court of Appeals despite opposition from California’s two Democratic home-state senators.

Lee’s nomination was approved by the Senate Wednesday in a 52-45 party-line vote. He is the 40th federal appeals court judge nominated by President Trump to be confirmed. Lee, 43, is replacing the late Judge Stephen Reinhardt, who was considered to be a liberal lion of the 9th Circuit.

The Senate moved forward with Lee’s confirmation over objections from California Sens. Dianne Feinstein and Kamala Harris, both Democrats. Neither Feinstein nor Harris returned their “blue slip” for Lee and had urged Senate Judiciary Committee Chairman Lindsey Graham, R-S.C., to pull his nomination because of “disregard for the vetting process and his failure to turn over requested material.”

[Previous coverage: Trump's chance to overhaul the liberal 9th Circuit]

The blue slip is a Senate practice under which home-state senators can voice their support or opposition to a judicial nominee on a blue form. Some past chairmen of the Senate Judiciary Committee have allowed home-state senators to effectively veto a nominee by not returning their blue slips, but under Graham, unreturned blue slips have not precluded nominees to the federal appeals courts from receiving confirmation hearings.

Lee was first tapped for a seat on the 9th Circuit last year. He came under fire from Democrats on the Senate Judiciary Committee for his college writings on sexual assault, race, and LGBT rights. Some of his writings were not initially turned over to the Senate panel, which prompted accusations from Senate Democrats that he lacked candor and should not be confirmed.

Before the Senate voted on Lee’s nomination, Feinstein, the top Democrat on the Senate Judiciary Committee, criticized his record and called it “far outside the mainstream.” She also took aim at Senate Republicans for moving forward with Lee’s nomination despite the unreturned blue slips.

Judge Kenneth K. Lee. (Screenshot/Fox News)

A blue slip from the Senate Judiciary Committee’s ranking member, Feinstein said, “has never been ignored before.”

The 9th Circuit is considered to be the country’s most liberal appeals court, and it has ruled against Trump in a number of cases challenging his policies, including the travel ban and roll back of the Deferred Action for Childhood Arrivals Program,

As a result of its rulings, the 9th Circuit is frequently the target of Trump’s ire. The president has referred to the federal appeals court as “unfair” and a “disgrace.”

But Trump has the opportunity to bring the 9th Circuit closer to parity. If the Senate confirms the president’s other two nominees to the court, Daniels Collins and Daniel Bress, 12 of the judges will have been appointed by Republicans and 16 by Democrats. One additional vacancy on the 9th Circuit remains.