Here's some advice for anyone following the U.S. midterm elections on Tuesday: Be ready for a long night and maybe days of waiting before it's clear whether Republicans or President Joe Biden's Democrats will control Congress, Reuters reported

All 435 seats in the U.S. House of Representatives are up for grabs, as are 35 U.S. Senate seats and 36 governorships.

Republicans would need to pick up five seats to take a majority in the House and just one to control the Senate. Nonpartisan election forecasters and polls suggest Republicans have a very strong chance of winning a House majority, with control of the Senate likely to be closer fought.

A massive wave of Republican support could lead to declarations of victory hours after polls close.

The first wave of vote tallies is expected on the East Coast between 7 p.m. and 8 p.m. ET Tuesday (0000-0100 GMT Wednesday).

It may take longer, perhaps weeks longer, to know which party will control the Senate, with close contests in Pennsylvania, Arizona, and Georgia likely to determine final control.