Based on the US election results, the situation looks like this. The last seat in the Senate will also go to the Democrats. The ratio will be 56 to 44, the Democrats' advantage will increase to 12 seats.
To end the war with Iran:
In the past, the Democrats were always one vote short. They will now have an advantage of 12 seats.
In the House of Representatives, the Democrats' advantage is also 83 seats.