A short-handed Supreme Court kicks off its new term Monday, albeit overshadowed by the drama over filling the seat of retired Justice Anthony Kennedy. But the court's upcoming decisions from its hot-button docket will likely have a far greater public impact than the politics of the moment.

If the White House and Senate Republicans get their way, Judge Brett Kavanaugh – who is fighting sexual assault allegations in his bid to take Kennedy’s seat – would be the 114th member of the Supreme Court. His impact could be felt right away, and for decades to come.

"He will assume a position of great importance, if not quite the same level as Justice Kennedy had" if he’s confirmed, said Thomas Dupree, a leading appellate attorney and former Bush Justice Department official. "A lot of times the judge you think you get doesn't turn out to be the judge you actually do get. But in Judge Kavanaugh's case I think we have a pretty good idea of where he’s going to come down on some of these issues."

That has many progressive groups worried a shaky conservative majority could solidify.

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"He will likely be the deciding votes on such issues as voting rights, reproductive choice and justice, the ability of everyday Americans to hold big business accountable," said Elizabeth Wydra, president of the Constitutional Accountability Center. "A majority on the Supreme Court with Justice Kavanaugh could vastly change the way American people live in this country."

That's if Kavanaugh is confirmed. His nomination advanced out of committee on Friday, but a new FBI supplemental background check reviewing the allegations against him -- set to be completed by Friday -- is underway.

Regardless, Kavanaugh will not be on the bench when the court holds oral arguments on the "First Monday in October," which by law marks the beginning of the new Supreme Court term.

Among the disputes scheduled to be argued this fall are those concerning the death penalty, smartphone apps and a closely watched-property rights case.

At issue in that case is the dusky gopher frog, an endangered species. Private land owners in Louisiana protest the government’s designation of “critical habitat” for the rare amphibian in that state, even though it is only known to exist in neighboring Mississippi.

But the justices in coming weeks are poised to add a range of other contentious issues to their caseload. Those include:

--A challenge to a "peace" memorial in the shape of a Christian cross that sits on government land to honor those servicemen killed in war

--Separate petitions over abortion, including waiting periods; restrictions on second-trimester procedures; and state Medicaid funding

--The validity of state-regulated surrogacy pregnancy contracts

--Lawsuits from environmental groups over the impact of President Trump's proposed border wall

--Continuing challenges to the administration’s immigration enforcement policies

--And the big what-if: whether the president can be compelled to testify in Special Counsel Robert Mueller’s Russia probe

"A subpoena for live testimony has never been tested in court as to the president of the United States," said Jay Sekulow, one of Trump's private attorneys, who threatened to challenge any such demand to the Supreme Court.

That has many Democrats worried Kavanaugh would protect the man who nominated him from any Mueller probe subpoena.

"Judge Kavanaugh's judicial philosophy incorporates an almost monarchial view of executive power and accountability," said Senate Minority Leader Charles Schumer, D-N.Y., "animated by the belief the chief executive gets to play by a different set of rules."

Roberts Rules

While the immediate focus will be on the newest member of the court – whether Kavanaugh or someone else -- many court watchers believe Chief Justice John Roberts is ready to assert his authority.

With Kennedy's departure, the man Trump once called an "absolute disaster" potentially is poised to inherit the mantle of "swing justice" – and solidify his power.

Whether Roberts can, or wants to, fill that vacuum is the big question in judicial circles right now.

Some right-leaning legal activists have long believed Roberts is not someone whose vote they can take for granted, despite the Republican-appointed 63-year-old chief justice having a mostly conservative record for 13 years.

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This was underscored after Roberts' dramatic 2012 deciding vote upholding the key funding provision of the Affordable Care Act -- saving then-President Barack Obama's signature domestic policy achievement.

Conservatives called it a calculated act of betrayal, a narrative Trump echoed on the 2016 campaign trail.

Some liberal leaders hold out tenuous hope Roberts takes a more active role as that "swing" vote – but there is conflicting evidence he would drift left with abandon.

Court sources have said Roberts has made a concerted internal effort over the years to promote consensus among his oft-divided colleagues, with as many unanimous rulings as possible to promote unity and comity.

He and his colleagues want to preserve the court’s independence and reputation.

"None of us wanted to look as if the court couldn't do its job," Justice Elena Kagan said Thursday. "I think we all felt as though the country needed to feel that the court was a functioning institution no matter what was happening outside."

High Stakes

The Supreme Court takes only those cases it wants to resolve, and typically only when there are differing legal interpretations in the lower courts. Because of that, the vast majority of appeals remain on the judicial back burner.

So in trying to insulate the third branch of government from the current wave of political slings, some legal experts say Roberts may use his authority to try -- in the short-term at least -- to avoid putting too many divisive cases before them.

"The court in the last few years is really become the decision maker of last resort on so many issues that have polarized our society ranging from what the president's power is, to constitutional rights, to resolving religious liberty claims," said Dupree. "So I think we'll see how broad a docket the Supreme Court wants this term, and how important they are to resolving these issues."

But with the Kavanaugh nomination coming on the eve of the midterm elections, the stakes over who sits on the Supreme Court, and how they decide, remains on the mind of voters.

"Because these issues are so hotly contested, and there are sharp divides among the electorate, you can’t help those issue seeping into our elections," said Wydra. "The fact is, whoever controls the Senate is going to have a big role in the kinds of judges ... put on the Supreme Court and the entire federal judiciary."