With Sen. John McCain (R-Ariz.) on sick leave, a single "no" vote by a Republican could ruin the confirmation. Doug Jones, D-Alabama, and Sen.
Kavanaugh worked on the effort by Bush's campaign to halt the recount of votes in Florida in the disputed presidential election between Bush and Al Gore in 2000.
Kavanaugh and Barrett had the inside track as of Thursday and Friday, as NPR first reported, but their supporters and opponents have gone after each other through the media and internally to the White House.
Trump said on Sunday he not made up his mind yet but expected to do so by noon on Monday, ahead of his announcement at 9 p.m.
Kavanaugh, a 53-year-old conservative-leaning federal judge for the past 12 years, is no stranger to executive branch politics and controversy. He is a fine husband, father, and friend - and a man of the highest integrity. "The Supreme Court is entrusted with the safeguarding of the crown jewel of our republic: the Constitution of the United States".
Still, some of the 1.2 percent of votes when Collins bucked a Republican president's nominee were notable.
Kavanaugh was appointed to D.C. Circuit appeals court in May 2006, after his nomination by President George W. Bush and his confirmation by the Senate.
The process is arduous, with the private meetings giving way to days of testimony before the Senate Judiciary Committee, which has 11 Republicans and 10 Democrats.
In anticipation of Trump filling the vacancy left by the retiring Anthony Kennedy - widely considered to be the court's "swing vote" - with a judge thought to have more conservative bona fides, many outside advocacy groups are already bracing for what will likely be a contentious confirmation battle.
"A year and a half ago, I said it was a top priority", he said about confirming judges, "and it remains so".
Democratic Senator Dianne Feinstein said Trump's choice "could have a bigger effect on Americans' daily lives than any justice in our lifetime". But, the officials said, McConnell did note that Hardiman and Kethledge could fare well in the Senate because their reputations and records were not as politically charged as others on the president's shortlist of nominees. "This is an opportunity for Senators to put partisanship aside and consider his legal qualifications with the fairness, respect, and seriousness that a Supreme Court nomination ought to command".
The source described Kavanaugh now as "a little risky" because of that, "and - perhaps, in the end - too establishment for DJT [Donald J. Trump]". Bob Casey (D-Pa.), who opposes abortion, announced on Monday he can not support a process that involved Trump's picking from a list of 25 candidates selected by conservatives and big business. "Justices who sit on the most important court in the world should not be selected by corporate interests and extreme right organizations".
McConnell said Kavanaugh believes judges should ignore their personal and political views and simply "interpret our laws as they are written". "If he proves as eager an executor of the president's bitter campaign to overturn Roe v. Wade and sabotage Americans' health care as his record suggests, a woman's right to choose will be repealed and the health coverage and economic security of 130 million Americans with pre-existing conditions will be in grave peril". Cornyn told reporters that he will join about 30 Senate Republicans at the White House prime-time announcement.
Any of the candidates on Trump's short list would probably move the court to the right.
Kavanaugh has never directly ruled on abortion as a judge, so it's unclear how he would decide the subject.
Critics accused Trump of outsourcing his selection to the conservative groups.
Kavanaugh, 53, had always been mentioned in Washington chatter as a potential high court choice by a Republican president because of his educational background, intellectual firepower and an unyielding commitment to a legal approach championed by conservative Supreme Court justices such as Clarence Thomas and Samuel A. Alito Jr.