Washington (CNN) President Donald Trump sought at a rally Saturday to mobilize his base over the contentious confirmation of Supreme Court Justice Brett Kavanaugh.

During his remarks in Montana, Trump dwelled extensively on Kavanaugh's confirmation -- and focused on a woman whose name and accusations had not come up publicly in a hearing to explore allegations of sexual assault and misconduct made against the judge.

In his speech, Trump referred to Senate Judiciary Committee Chairman Chuck Grassley's Friday referral of a woman's previously unreported allegations of sexual assault against Kavanaugh for a Justice Department and FBI investigation -- allegations that the woman later admitted were false, according to Grassley.

Trump used the referral to cast doubts about the allegations that other women, including Christine Blasey Ford, have made against the now-Supreme Court justice.

Trump did not draw a distinction between the Grassley referral of a woman who had received little attention and the allegations of Ford and other women who made claims to the Senate Judiciary Committee.

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