Mr. Trump is set to announce his pick for the vacancy left by retiring Justice Anthony Kennedy at 9 p.m. Monday.
"He's a brilliant jurist with a clear and effective writing style, universally regarded as one of the finest and sharpest legal minds of our time".
Republican Sens. Lindsey Graham of SC and Roy Blunt of Missouri said Sunday that they believe any of the top four contenders could get confirmed by the GOP-majority Senate. He also stressed that the constitution must be interpreted "as written - informed by history and tradition and precedent".
He served with Judge Maryanne Barry, President Trump's sister.
"Throughout legal circles he's considered a judge's judge, a true thought leader among his peers", Trump, who named conservative Justice Neil Gorsuch to the court previous year, told an applauding audience in the White House East Room.
The 53-year-old Kavanaugh, who clerked for Kennedy and who now sits on the USA court of appeals for the D.C. Circuit Court, emphasized in his remarks accepting the nomination the importance of judicial independence.
The Republican president, with an opportunity to further put his stamp on the court with the second appointee of his 18 months in office, is expected to choose among four judges with strong conservative credentials: Thomas Hardiman, Brett Kavanaugh, Raymond Kethledge and Amy Coney Barrett.
Judge Kavanaugh now faces what could be a hard fight for confirmation by the US Senate, where Republicans hold only a slim majority. Three Democrats up for re-election in states Trump won by double digits in 2016 - Indiana Sen. Others have expressed concern about how Kavanaugh would vote on cases related to the health care law. Sen.
Democrats and liberal advocacy groups quickly lined up in opposition.
Trump has previously said he wanted "pro-life" justices opposed to abortion rights. Some, like Democratic SEn.More news: In Canada, 33 people died from the heat wave
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Barrett talks about her family in her introductory remarks to the Senate Judiciary Committee. "Maybe a handful of Democrats will vote for a Trump pick because they have to politically".
Republicans hold 51 seats in the Senate, though Arizona Sen.
Meanwhile, liberal groups are already calling on two moderate Republican senators - Susan Collins of ME and Lisa Murkowski of Alaska - to reject the nominee. The two have supported access to abortion services. At the top of that list is abortion.
Like the other eight justices on the court, Kavanaugh has an Ivy League law degree, spending his undergraduate and law school years at Yale.
FILE PHOTO: The U.S. Supreme Court is seen as the court nears the end of its term in Washington, U.S., June 11, 2018. He also worked on independent counsel Ken Starr's investigation of President Bill Clinton.
Kyl's registered lobbying clients this year have included Qualcomm Inc., JW Aluminum, mining company Freeport-McMoRan, the Coalition for American Retirement and the private equity investor Gordon Sondland, who is co-founder of Aspen Capital, according to congressional lobbying disclosures.
In his dozen years on the court, Kavanaugh has been involved in some 286 opinions.
Kavanaugh's views on presidential power and abortion are expected to draw particular attention in his confirmation hearing. He laid out the legal framework supporting Clinton's impeachment for his affair with then-White House intern Monica Lewinsky.
Senator Dick Durbin (D-Ill.) questions Barrett on her Catholic faith and whether it would influence her decisions on the federal appeals court in her Senate confirmation hearing, September 6, 2017.
A confirmation for Judge Kavanaugh would mean "women's reproductive rights would be in the hands of five men on the Supreme Court", he added.