It would require an amendment to article 1, section 3 of the US constitution which explicitly requires that senators should serve staggered terms, with 1/3 of t

It would require an amendment to article 1, section 3 of the US constitution which explicitly requires that senators should serve staggered terms, with 1/3 of the senate up for reelection every 2 years. This was done intentionally to make it difficult for the Senate membership to be swept in a landslide at the same time as the House, which can happen to the House every two years. Compared to the House, the Senate was intended to be a more deliberative body, changing its composition on a longer timescale, and less responsive to short-term political opinion. Whether or not that works as intended is certainly debatable, but every time we change the Senate to work more like the House it raises the question of why we should bother having a bicameral legislature if both chambers are increasingly similar.