Where Kavanaugh, Trump’s Nominee, Might Fit on the Supreme Court

In choosing Brett M. Kavanaugh, 53, to replace Justice Anthony M. Kennedy, President Trump opted for a Washington insider who, according to at least one measure, may be less conservative than Mr. Trump’s first Supreme Court nominee, Neil M. Gorsuch.

According to an analysis based on political donations given before becoming a federal judge, Judge Kavanaugh is estimated to be more conservative than 66 percent of all other current and former federal judges nominated since 1980. Using the same measure, Justice Gorsuch was estimated to be more conservative than 85 percent. About 19 percent of Judge Kavanaugh’s donations went to Richard Cordray, a Democrat who worked with him at a Washington law firm.

If confirmed, Judge Kavanaugh, who is expected to be a reliable conservative, would replace Justice Kennedy, a Reagan appointee who often voted with the court’s liberal wing on social issues like abortion and gay rights.

With Judge Kavanaugh’s nomination, Mr. Trump has followed a more recent trend of picking judges who previously served as federal officials or judges in Washington, D.C. — those who are more likely to vote consistently with the ideology of the president who appointed them.

Before joining the United States Court of Appeals for the District of Columbia Circuit, Judge Kavanaugh held several posts in the administration of George W. Bush, ultimately serving as his staff secretary. He also worked under Kenneth W. Starr, the independent counsel who investigated President Bill Clinton.

“Justices with D.C. experience are less likely to drift because presidents have much more information about who they are appointing,” said Lee Epstein, a law professor and political scientist at Washington University in St. Louis.