♪ reporter: in just a few hours congress will be convening to certify the results of the electoral college and confirm president-elect joe biden's victory. reporter: crowds are already gathering for a pro-trump rally that the president says he will speak at. as many as 30,000 people expected- reporter: this is a day that happens every 4 years that usually no one pays attention to, but this year all eyes are on capitol hill. reporter: dozens of house and senate republicans are going to object to the certification of millions of legally cast votes. reporter: still the president is ramping up pressure on vice president pence to flip the outcome, even as pence himself reportedly told the president that he does not have that power. trump allies tell nbc news, they believe he will keep disputing the results, what allies say the president is increasingly desperate. ♪