WASHINGTON - The White House does not want to see a prolonged impeachment trial in the US Senate, a senior administration official said on Sunday, suggesting President Donald Trump is comfortable with proceeding without calling witnesses in his defense.The Democratic-led House of Representatives approved two impeachment charges against Trump on Wednesday over his pressuring of Ukraine to investigate a political rival. There is little chance he will be convicted and removed from office through a trial in a Senate controlled by fellow Republicans.Democrats are pressing to call top Trump aides to testify, but Senate Majority Leader Mitch McConnell wants the Senate to consider the case without hearing from new witnesses.While Trump had indicated an interest in calling separate witnesses in his defense, he has also said he would go along with whatever decision McConnell and other Senate Republican leaders make.In remarks on Sunday talk shows, Marc Short, chief of staff to Vice President Mike Pence, indicated the White House was on board with McConnell's goal of a speedy trial."The American people are tired of this sham," Short said on NBC's "Meet the Press.""To the extent that there's a prolonged trial, we're not anxious about that," he said. "Our administration is anxious to get back to working for the American people ... We've had a lot of witnesses already."Lawmakers left Washington for a holiday break on Friday at loggerheads over how to proceed.To ramp up pressure on McConnell to permit new testimony, House Speaker Nancy Pelosi - the top Democrat in Congress - has postponed sending the impeachment charges to the Senate.Republicans have suggested Democrats want witnesses because the case they have assembled is so weak, while Democrats portray Republicans as scared about what new testimony might reveal."If her case is so air tight ... why does she need more witnesses?" Short said on "Fox News Sunday."Speaking to reporters in New York, Senate Democratic leader Chuck Schumer stuck with Democrats' position that further testimony was required. "It's a sham trial and that's why we feel so strongly there ought to be witnesses and documents," he said.REPUBLICAN MODERATESTrump is only the third US president in history to be impeached. The others were Andrew Johnson in 1868 and Bill Clinton in 1998. Richard Nixon resigned in 1974 as he faced the threat of impeachment.The House charged Trump with abusing his power by holding back $391 million in security aid to Ukraine in an effort to get Kiev to announce a corruption investigation of former Vice President Joe Biden, a leading candidate for the Democratic nomination to face Trump in the November 2020 election.Trump was also charged with obstructing Congress by directing administration officials and agencies not to cooperate with the impeachment inquiry. He says he did nothing wrong and has dismissed his impeachment as a partisan bid to undo his 2016 election win."The American people and the United States Senate deserve to have a full, fair and complete trial and that means witnesses, it means documents," Democratic Senator Doug Jones told ABC's "This Week."Responding to Republican charges that the case was thin, Jones said that if it was thin, "it's thin because the president of the United States ordered his top people who were in the room who have first-hand knowledge, not to testify."Republicans hold a 53-47 majority in the Senate, and Democrats are hoping a few moderate Republicans will support their bid for further testimony and force McConnell's hand."The leverage is our hope that four Republican senators will stand up ... and say this is much bigger than our current political squabbles," Dick Durbin, the No. 2 Democrat in the Senate, told CNN's "State of the Union.""If four Republican senators step up, it can make a big difference," he said.