WASHINGTON — Senate leaders remained at an impasse Thursday over the scope of an impeachment trial of President Trump, as his re-election campaign claimed that a backlash from the House proceedings had helped him raise $46 million in the final months of 2019.

Aides to Senate Majority Leader Mitch McConnell, R-Ky., and Senate Minority Leader Chuck Schumer, D-N.Y., said thy hadn’t spoken over the holidays about the standoff.

House Speaker Nancy Pelosi, D-Calif., has held off sending the two articles of impeachment – for abuse of power and obstruction of Congress – to the Senate.

At the heart of the Democrats’ case is the allegation that Trump tried to leverage a White House meeting and military aid, sought by Ukraine to combat Russian military aggression, to pressure Ukrainian President Volodymyr Zelensky to launch an investigation of former vice president Joe Biden and his son Hunter Biden.

Schumer on Thursday seized on a new report that cited unredacted emails that bolster the case that Trump was directly involved in withholding military aid to Ukraine as he was seeking investigations that could benefit him politically.

The report by Kate Brannen was published by Just Security. It referenced an email from Michael Duffey, associate director of national security programs at the Office of Management and Budget, to Elaine McCusker, the acting Pentagon comptroller, on Aug. 30, a little more than a month after Trump pressed Zelensky for investigations during a July phone call.

In the email, which followed a meeting with Trump that included senior administration officials, Duffey told McCusker, “Clear direction from POTUS to hold.”

Schumer has sought guarantees from McConnell that several administration officials will be subpoenaed to testify in a Senate trial who declined to participate in House impeachment proceedings, including Duffey. McConnell has said the Senate should decide on what if any witnesses to call after hearing opening statements.