(Bloomberg Opinion) -- Four of the last 14 vacancies on the Supreme Court arose when different parties controlled the White House and a majority in the Senate. In those cases, the president’s initial nominee didn’t make it through half the time. When the president and the Senate were allied, on the other hand, 9 of 10 initial nominees were confirmed.

That’s the simplest explanation for why Judge Amy Coney Barrett is about to be confirmed to the Supreme Court: Republicans have the votes. What the balance of power doesn’t explain is rising public support for Barrett.

The Morning Consult has found a steady increase in the percentage of voters favoring her confirmation. If the polls had instead turned against her, a few Republican senators might have gotten nervous enough to stop her nomination. But that didn’t happen.

When Justice Barrett writes her thank-you notes, the first one should go to Democratic Senator Dianne Feinstein, and not for the hug she gave Republican Senator Lindsey Graham for his handling of the recent Judiciary Committee proceedings. In 2017, during hearings over Barrett’s confirmation to an appellate court, the California Democrat infamously made a snide remark about the nominee’s Catholic faith: “The dogma lives loudly in you.”

Feinstein’s aides made criticisms of Barrett based on their unfamiliarity with basic Christian terms such as “the kingdom of God.” Feinstein’s attack drew widespread condemnation: Christopher Eisgruber, the president of Princeton University, who is neither conservative nor Catholic, wrote a letter decrying it.

Feinstein made Barrett a heroine to politically engaged conservatives nationwide. The controversy wouldn’t have been enough to get her on the Supreme Court short list. But it got more influential conservatives to take a look at her intellect and accomplishments. No senator did more to get Barrett the Supreme Court nomination than Feinstein.

When Barrett got it, Republicans were ready. They warned that Democrats would attack the nominee’s religion. Senate Democrats, including Feinstein, avoided repeating her mistake. But they were also inhibited from making the case that Barrett is a social-issues extremist, and when they did it was easier for Republicans to associate their accusation with religious bigotry.

Their main argument against Barrett was instead based on procedure. They said that it was improper to confirm a justice during a presidential election, and that Republicans were hypocrites for doing it after denying President Barack Obama the chance to fill a vacancy in 2016.

None of this had anything to do with Barrett herself. Voters could be persuaded that the Democrats were right about all of it without becoming convinced that putting Barrett on the court was in any way dangerous.

In 1987, Senator Ted Kennedy defeated a nomination by painting a frightening picture of “Robert Bork’s America.” In 2018, Democrats nearly succeeded in defeating Brett Kavanaugh’s nomination after accusing him of everything from perjury to sexual assault. In 2020, in the heat of the first presidential debate, Joe Biden said of Barrett: “I’m not opposed to the justice; she seems like a very fine person.”

The ongoing election campaign ended up turning the temperature down on the hearings. Democratic senators, knowing that she was likely to be confirmed, spent their questioning time scoring points against Trump and Republican senators at least as much as they did trying to make Barrett look bad.

The Democrats also played their weak hand badly. Early talk of boycotting the hearings came to nothing. A boycott would not have been effective — but might still have been better than what the Democrats did, which was to participate in the hearings and then call them illegitimate.

Barrett performed well at the hearings. She was greatly aided by the convention that court nominees not share their views on disputed constitutional issues — a convention she interpreted expansively. The senators never flummoxed her, never got her to make a gaffe. She didn’t come across as an ideologue or a cold know-it-all.

Instead, she came across exactly as one would have expected after reading the American Bar Association’s evaluation of her nomination to the Supreme Court. It reported, “Most remarkably, in interviews with individuals in the legal profession and community who know Judge Barrett, whether for a few years or decades, not one person uttered a negative word about her character.” By the end of the hearings, Barrett’s opponents were reduced to complaining about the good impression she makes.

Meanwhile, Republicans were vigorously and consistently arguing for Barrett, while Democrats sporadically and limply argued against her. That blank page of notes she held up might as well have been a list of all the Democratic criticisms of her that connected with the public. And that’s why she is soon to be just what Biden’s slip of the tongue foretold: Justice Barrett.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Ramesh Ponnuru is a Bloomberg Opinion columnist. He is a senior editor at National Review, visiting fellow at the American Enterprise Institute and contributor to CBS News.

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