Democrats warned that US President Donald Trump was on the verge of dictatorship while Republicans fiercely defended his record at the opening of a stormy, historic debate on his widely publicised impeachment charges Wednesday.Wednesday was the beginning of a two-day debate. Trump is alleged to have wielded the power of the presidency for personal and political gain by pressuring Ukraine to interfere in the 2020 US election.There is little question about the outcome in the House Judiciary Committee: by the end of the week the majority Democrat panel is expected to approve the charges and send them to the entire House of Representatives for passage next week.But lawmakers in the televised hearing appeared focused on speaking to voters, whose sentiment will be crucial if, as expected, Trump goes on trial in the US Senate in January.Democratic committee chairman Jerry Nadler opened the hearing.Two articles of impeachment against Trump will be considered.ALSO READ | Democrats lay out impeachment case against Trump"Taken together, the two articles charge President Trump with placing his private political interests above our national security, above our free and fair elections, and above our ability to hold public officials accountable," he said."If the president can first abuse his power and then stonewall all congressional requests for information, Congress cannot fulfill its duty to act as a check and balance against the Executive - and the president becomes a dictator."Charges 'generic, vague'Doug Collins, the senior Republican on the committee, argued that Democrats have been seeking to impeach Trump ever since he came into office in January 2017, and have no clear case beyond "abuse of power.""It's just generic vague statements," Collins said."This is as much about political expediency as it is anything else, and that should never be an article of impeachment."Trump faces becoming only the third president in US history to be impeached and placed on trial in the Senate.ALSO READ | Top Democrat squares up for Trump impeachment, President remains defiantHe is accused of pressuring Ukraine for help against his Democratic challenger Joe Biden ahead of next year's national elections, and holding up military aid to the country which it needed to face Russian aggression, unless it did his bidding.Republicans stick behind TrumpJim Jordan said Democrats were simply refighting their 2016 election loss and hated Trump."This is about one basic fact: the Democrats have never accepted the will of the American people," he said. "They don't like the 63 million people who voted for this president.""Will we hold the president accountable, or will we serve as his accomplices?" Hank Johnson, from the Democrats fired back.Most indications are that the Republican majority in the Senate will ultimately protect Trump from conviction and removal.But impeachment could mar his record as president and affect his reelection chances in November 2020.