Sens. Charles E. Schumer and John McCain said Monday they are calling for a bipartisan investigation into recent reports that the CIA concluded Russian hackers actively tried to boost President-elect Donald Trump’s chances in the election — a conclusion Mr. Trump summarily dismissed on Sunday.

“There’s no doubt about the hacking — let’s establish that,” Mr. McCain said on “CBS This Morning.” “Then the question is about the intention.”

Mr. McCain, Arizona Republican, said he couldn’t yet reach the conclusion that the hacking was done explicitly to help Mr. Trump and said that’s why an investigation is warranted.

He said the Senate Armed Services Committee, which he chairs, will look into the broader issue of overseas cyber threats.

“This is serious stuff when a foreign power tries to influence our election or damage our economy, for that matter,” said Mr. Schumer, New York Democrat and the incoming Senate minority leader. “This is serious … a bipartisan investigation that’s not aimed at one specific instance but looks at the broad scope of this is just what’s needed.”

Several recent news reports, citing CIA officials, said the intelligence agency believes Russia tried to tip the scales in Mr. Trump’s favor during the presidential election through, for example, the hacking of private communications of Democratic National Committee and Clinton campaign officials.

Many of the private communications, notably to and from Hillary Clinton’s campaign chairman, were released on a rolling basis by the website WikiLeaks.

Mr. Trump has rejected such findings, telling Fox News Sunday he thinks it’s just another excuse for Mrs. Clinton’s loss.

On Monday, former Trump campaign manager Kellyanne Conway said Mr. Trump “respects” the intelligence community.

“The president-elect does not want interference into our politics, but we also don’t want politics into the interference of our intelligence, and that’s what’s happening now,” Ms. Conway said on ABC’s “Good Morning America.” “People are trying to politicize our intelligence because they don’t like the election result.”