US election: The fight for control of Congress

The battle for the White House is not the only important US election taking place on November 5th. “Down-ballot” races for everything from state governors to small-town officials will also be held. The most important of these are the contests to control the two houses of Congress, the lower house (House of Representatives) and the upper house (Senate). Whoever is elected president, if their party does not hold a majority in both houses, their scope for implementing policy will be severely limited.
The rules for electing the two chambers are quite different. The House of Representatives is made up of 435 elected members divided among the 50 states in proportion to their population. Elections to the House take place every two years, with all seats contested. With 220 seats, Republicans currently hold a slim majority and Democrats will be seeking to regain control. With only a small swing of five or six seats required, they will be targeting seats they lost to Republicans in 2022 in states such as New York and California.
For the 100-seat Senate, each state elects two senators, regardless of population size. So California (population 40 million) has the same number of senators as Wyoming (population 600,000). Senators serve for six years, with one third of Senate seats up for election every two years. Democrats currently have a majority of one in the Senate (and in the event of a tie vice-president Kamala Harris wields the casting vote).
Democrats have a reasonable chance of regaining the House but face an uphill battle to hold on to their Senate majority this November. Of the 34 seats scheduled for election this time around, 23 are held by Democrats. Some of these seats are in heavily Republican states such as Montana, Ohio and West Virginia. Others are in swing states such as Michigan and Pennsylvania. By contrast, Democrats have only a faint hope of dislodging a couple of Republican incumbents in states such as Florida and Texas, which are almost certain to vote for Donald Trump for president. Polling analysts give Republicans a 75 per cent chance of winning a Senate majority.
Control of the House and Senate will be important for whoever ends up in the White House. While a US president has wide-ranging executive powers over the day-to-day running of the federal government, and has considerable leeway in determining foreign policy, other areas – most importantly tax and government spending – require approval from Congress. Members of the House also have powers to conduct investigations, call witnesses and ultimately even impeach a president (as happened twice to Donald Trump), although the final sanction in that instance remains with the Senate, which can also block presidential appointments, including to the supreme court, while having the final say on any important legislation.