■ President-elect Donald J. Trump wrote on Twitter that a dossier of unsubstantiated Russian dirt on him was “fake news” and “a total political witch hunt.”

■ Democrats are already seeking classified briefings on the dossier’s conclusions and validity.

■ A key Republican senator is pressing to slow down his party’s effort to repeal the Affordable Care Act.

From the moment the unsubstantiated but explosive intelligence report hit the internet, the questions arose: When and what would Mr. Trump tweet?

Shortly after 8:15 p.m. on Tuesday, the world had its answer.

Mr. Trump’s longtime lawyer and sometimes spokesman, Michael Cohen, followed with his own defense, a possibly ill-advised reference to Page 18 of the dossier, which alleges a secret meeting between Mr. Cohen and Russian intelligence agents in Prague — not something the Trump team wants attention on.

Mr. Trump retweeted that, as well.

Kellyanne Conway, a senior adviser to Mr. Trump, took another tack. Asked by the late-night talk show host Seth Meyers about the briefing intelligence officials had given Mr. Trump on the matter, she said she was not aware that he had been briefed.

Questions continue to swirl about the validity of the dossier alleging that Russian intelligence has deeply compromising material on the man who is about to be commander in chief. But its wide circulation has already had an impact.

On Tuesday night, Representative Brad Sherman, Democrat of California, asked President Obama for a classified briefing on “the compromising information Russia has obtained regarding President-elect Donald Trump.”

His request will not be the last.

Mr. Trump may be demanding an immediate repeal of the Affordable Care Act and a simultaneous enactment of a Republican replacement — and the House speaker, Paul D. Ryan, may be concurring with that rush — but one senator is not on board. And he is an important one.

Senator Lamar Alexander of Tennessee, chairman of the Senate Health, Education, Labor and Pensions Committee, addressed the headlong rush on Tuesday night. “The American people deserve health care reform that’s done in the right way, for the right reasons, in the right amount of time,” he said. “It’s not about developing a quick fix. It’s about working toward long-term solutions that work for everyone.”

That is significant. If, as expected, Congress passes parliamentary language in the coming days to protect repeal legislation from a Democratic filibuster, four committees will be empowered to draft the actual bill. Mr. Alexander leads one of those committees.