WASHINGTON — The Senate Armed Services Committee will convene on Thursday morning for a hearing on “foreign cyberthreats to the United States.” Of course, one foreign entity is destined to loom largest: Russia.

The hearing arrives at an explosive moment. President-elect Donald J. Trump has continued to express doubts about Russia’s interference in the presidential election, placing him at odds with the intelligence agencies he will soon command and with several leading members of his own party.

Here is what to watch for Thursday on Capitol Hill:

Senator John McCain, Republican of Arizona, the committee’s chairman, has made no secret of his belief that Russia was responsible for the election-related hacking, and his recent travels will not have eased his concerns about Russian aggression. He just returned from a New Year’s tour of countries that see themselves as threatened by Russia: Ukraine, Georgia and the Baltic republics of Estonia, Latvia and Lithuania.

Senator Jack Reed of Rhode Island, the ranking Democrat, also has taken a strong public stand in support of the intelligence agencies’ finding of Russian government interference. He noted on Twitter:

The group will hear testimony from James R. Clapper Jr., the director of national intelligence; Marcel Lettre, the under secretary of defense for intelligence; and Adm. Michael S. Rogers, a leader of the National Security Agency and United States Cyber Command.

Other Republicans on the committee include Senator Lindsey Graham of South Carolina, a close McCain ally and fellow hawk on Russia, and Senator Ted Cruz of Texas.

On the Democratic side, members include Senator Elizabeth Warren of Massachusetts, who is making her hearing debut after being named to the committee.

He has a tower in Manhattan.

Most Republicans have avoided attacking Mr. Trump directly over his comments — even as he defended the credibility of Julian Assange, the founder of WikiLeaks, at the expense of the intelligence agencies. But the hearing will offer a potent showcase for the agencies to defend their work.

They are likely to face little hostile questioning from lawmakers.

“The point of this hearing is…