At his Senate confirmation hearings next week, Supreme Court nominee Judge Brett Kavanaugh is not expected to offer any commitment to recuse himself from cases involving investigations of President Trump, including a possible constitutional fight over a subpoena of the president, sources familiar with Kavanaugh's preparations tell ABC News.

Senate Democrats say they plan to press Kavanaugh over recusal during questioning. "He doesn't believe a sitting president should be investigated or prosecuted -- in other words, is above the law," Sen. Dianne Feinstein, the top Democrat on the Senate Judiciary Committee, said Friday.

"Pledging a decision on a particular matter or case – including the decision whether to hear the case – for political reasons, like obtaining confirmation votes, would violate the bedrock constitutional principle of judicial independence," said deputy White House press secretary Raj Shah, who is overseeing the administration’s Kavanaugh confirmation strategy.

Democrats have said they plan to use the confirmation hearings to spotlight Kavanaugh’s potential legal and ethical conflicts should Mueller bring any case involving the president before the high court. As part of that strategy, Democrats announced former White House Counsel John Dean, who helped bring down former President Richard Nixon, will testify as an outside witness.

Kavanaugh will “pledge to be independent-minded in the event he has to make such a consideration, as all justices do," a White House official involved with the process told ABC News. It's unlikely such an assurance will placate Democrats' concerns, though their ability to block the nomination remains limited.

Supreme Court nominees don’t typically engage in hypothetical scenarios, and it is not entirely surprising that Kavanaugh would decline to offer a firm pledge to recuse himself in any case, although other nominees have done so on specific matters. But Democrats will no doubt seize on such a moment in the hearings to try to validate their claims that Trump picked Kavanaugh with an expectation he would protect him from legal jeopardy.

Kavanaugh's public stance on executive authority will be a key topic during the hearings. He has favored fewer restraints on presidential power and advocated the idea that presidents should be free from the “distractions” of lawsuits or investigations while in office.

"Having seen first-hand how complex and difficult that job is, I believe it is vital that the President be able to focus on his never-ending tasks with as few distractions as possible,” Kavanaugh wrote in a 2009 Minnesota Law Review article. Kavanaugh suggested Congress could pass a law shielding presidents but added they could be made to answer once out of office, saying “no one is above the law.”

Democrats have pounced on that view to claim Kavanaugh’s judicial philosophy could enable Trump to avoid having to testify in Mueller’s probe into Russian interference in the 2016 presidential election.

“He chose the one person that has written that he should have immunity from any investigation and from any kind of prosecution that might result,” Cory Booker, D-N.J., said. “Every Republican and Democrat should come together with the insistence that Kavanaugh should recuse himself.”

Although Kavanaugh once helped write independent counsel Kenneth Starr’s report, which outlined broad grounds on which to impeach President Clinton for his role in the Monica Lewinsky scandal, Kavanaugh wrote in the law review article that his views have since evolved, and critics argue that could have significant implications for President Trump.

“The law as it existed was itself the problem, particularly the extent to which it allowed civil suits against presidents to proceed while the President is in office,” Kavanaugh wrote in 2009, reflecting back on the Clinton investigation. It was a civil lawsuit that initially sparked that investigation.

But Democrats are sure to highlight a memo Kavanaugh wrote Starr at the time that reveals he pushed a hard line in the investigation and questioning of Clinton, including asking about of graphic details about his sexual relationship with intern Monica Lewinsky.

Kavanaugh insists in the memo from August 1998 – ahead of a sit down with Clinton – that the president should not get any “break” and needed to provide “full and complete” testimony regarding their sexual encounters. Democrats will ask Kavanaugh why Trump should not be held to the same standard he advocated back then.

Kavanaugh’s nomination has also sparked concern on the left over his positions on issues like abortion rights, affirmative action, gay rights and other social issues.

The White House and Senate Republicans have been preparing for the coordinated Democratic onslaught against the nominee.

Kavanaugh has had a vigorous schedule since being nominated – sitting with a total of 65 senators in meetings that have lasted roughly 30 minutes each, a White House official told ABC News. He’s met with multiple Democrats on the Senate Judiciary Committee, which has helped the team tasked with preparing him for the hearings in gauging what to expect from both sides of the aisle.

“The hearing hasn’t even taken place, but the loudest Democrats are so set on obstruction that they’ve already said they’ll vote no,” RNC Chairwoman Ronna McDaniel said in a statement. “We’re going to make sure the American people know about the Democrats’ unprecedented level of resistance to this highly-qualified, mainstream nominee.”

The official said the White House has held at least two full-day sessions of mock hearings with Kavanaugh in the Eisenhower Executive Office Building – located adjacent to the White House – from 9 a.m. until 6 p.m. -- with only an hour break for lunch. Separately, the official said, there’ve been about six or seven sessions with him that have lasted nearly five hours – each session hitting on the potential subjects he’s likely to be pressed on during confirmation hearings.

The mock sessions are very much modeled after the confirmation hearings of Neil Gorsuch, Trump’s first pick to fill the slot left open by Justice Antonin Scalia. The team has re-watched and taken extensive notes on exchanges between Gorsuch and Judiciary committee members, with one official comparing it to when football teams watch tapes of their opponents prior to game day.

The Republican National Committee is also prepared to push back on Senate Democrats’ claims that Kavanaugh thinks a president should be immune from prosecution.

The RNC has previously cited a Washington Post article pushing back on the Democrats' claims that the matter is clear-cut and plans to do so again if the issue comes up, the official said.

The RNC has been working closely with the White House, allies of Capitol Hill and outside groups in their efforts, and has prepared a “war room” tasked with spearheading the rapid response and research operations, according to an RNC official.

The RNC plan has also already been focusing on states that President Trump won in 2016 where there is a Democratic senator up for re-election.