Support for Brett Kavanaugh, the Supreme Court nominee, has fallen to its lowest levels since President Donald Trump announced his selection in July, according to new polling.

Opposition to Kavanaugh's nomination now exceeds support for the nominee, two new polls found.

One poll found that support for Kavanaugh among Republican women had dropped by 18 points amid allegations of sexual misconduct against the judge.

Support for Brett Kavanaugh, the Supreme Court nominee, has fallen to its lowest levels since President Donald Trump announced the pick in July — and Republican women are a key reason.

Opposition to Kavanaugh's nomination now exceeds support for it, two new polls have found.

An NPR/PBS NewsHour/Marist poll, conducted Saturday through Monday, found that 43% of respondents said they oppose his nomination and 38% said they support it.

And a new Morning Consult poll, conducted Thursday through Sunday, found that 37% of respondents said they oppose the nomination and 34% said they support it.

Morning Consult found that Kavanaugh saw an 11-point drop in net support among Republicans over the past week — including an 18-point drop in net support among Republican women. Overall, 58% of GOP voters surveyed said they support his confirmation to the country's highest court, while 11% said they oppose it.

Morning Consult also found that GOP support for Trump dropped alongside support for his Supreme Court pick, falling by 16 points since a similar poll last week. Among Republican women surveyed, support for the president dropped by 19 points, with 68% saying they approve of him and 26% disapproving. (The poll's results for Republican voters have a 4-point margin of error.)

Both polls were conducted before Julie Swetnick came forward on Wednesday with allegations that Kavanaugh participated in plying teenage girls with drugs and alcohol so that they could be "gang raped" at high-school house parties in the early 1980s. She is the third woman to publicly accuse him of sexual misconduct. He has denied all the allegations.

Kavanaugh and Christine Blasey Ford, who has accused him of sexual assault, are scheduled to testify before the Senate Judiciary Committee on Thursday. The Marist poll found that nearly 60% respondents said they planned to follow the proceedings closely.

That poll also found that about a third of Americans (32%) said they believe Ford, while 26% said they believe Kavanaugh, and 42% said they don't know who to believe.

Most respondents in the Marist poll (60%) said that if Kavanaugh did indeed assault Ford, he should not be confirmed to the Supreme Court. Fifty-four percent of respondents who identified as Republican said the judge should be confirmed even if the allegations of sexual misconduct are true.

The poll found that public opinion is markedly more supportive of the accuser in this case than it was in 1991, when the law professor Anita Hill accused Clarence Thomas, a Supreme Court nominee at the time, of sexual harassment in the workplace. She testified before the Senate Judiciary Committee then too, in a highly publicized spectacle.

The Morning Consult poll surveyed 1,966 registered voters and has a margin of error of plus or minus 2 percentage points. The Marist poll surveyed 997 adults and has a margin of error of plus or minus 3.9 points.