Senate Democrats criticized the withholding of documents ahead of Tuesday's start of confirmation hearings for President Donald Trump's Supreme Court nominee Brett Kavanaugh, even as a top Republican predicted he would be approved by a healthy margin.

Senate Minority Leader Chuck Schumer of New York said in a tweet that the decision to hold back more than 100,000 pages of documents from Kavanaugh's work in President George W. Bush's administration was unprecedented for nominees and "has all the makings of a cover up." Dick Durbin of Illinois, the No. 2 Senate Democrat, said only 6 percent of material requested will be released "if we are lucky."

"If he's so proud of his conservative credentials, show us the record, stand before us, trust the American people and they will trust you," Durbin said on "Fox News Sunday."