Why are only some US Senate seats up for grabs? What to know in 500 words

Thirty-four of the 100 full Senate seats are being contested successful November, the effect of a staggered predetermination system.

One contention has dominated this year’s predetermination rhythm successful the United States: the conflict betwixt Kamala Harris and Donald Trump to triumph the White House.

But connected November 5, Americans besides volition ballot to capable different cardinal posts extracurricular the presidency. Many of those races will find who controls Congress, an important lever of power.

One-third of the US Senate is up for grabs, arsenic good arsenic the full House of Representatives. That amounts to 34 seats successful Congress’s precocious enclosure and 435 successful the little one.

But wherefore are representatives voted connected each 2 years — and senators each six? And wherefore aren’t each 100 seats successful the Senate contested astatine once, similar successful the House?

Staggered races successful the Senate

The reply goes backmost to the country’s founding, erstwhile the men who wrote the US Constitution decided to basal Senate elections connected a “three-class system”.

According to a Senate factsheet, “at the commencement of the archetypal league of Congress successful 1789, senators were divided into the 3 classes by batch with same-state senators assigned to abstracted groups”.

The archetypal radical saw their word expire successful 2 years, the 2nd successful 4 and the 3rd successful six years.

“Subsequent elections to each classes were for a afloat six-year Senate term,” the factsheet explains.

The thought was to springiness stableness to US politics. As a effect of the Senate’s staggered voting system, two-thirds of the senators stay successful their posts each clip a nationalist predetermination happens, erstwhile each 2 years.

How does this comparison to the House of Representatives?

Things are antithetic successful the little enclosure of Congress, wherever each of its 435 members service two-year presumption and are up for predetermination astatine each vote.

Having to basal for re-election each 2 years makes members of the House more susceptible to losing their seats.

Nevertheless, immoderate representatives person been successful the House for decades: Former House Speaker Nancy Pelosi, for example, has served for 37 years.

What could hap connected November 5?

The Democratic Party presently has a bladed grip connected the Senate. The enactment and allied independents clasp 51 seats, compared with 49 seats held by Republicans.

To instrumentality power of the chamber, Republicans request a nett summation of 1 Senate spot if Trump defeats Harris successful the statesmanlike race.

That’s due to the fact that the vice president acts arsenic the tie-breaking ballot successful the Senate. If Republicans triumph the White House, Trump’s running-mate JD Vance would capable that relation and ballot with Republicans.

If Harris wins — giving her vice president, Tim Walz, that tie-breaking powerfulness — past Republicans would request a nett summation of 2 Senate seats to summation control.

Of the 34 Senate seats being contested adjacent month, 23 are held by Democrats oregon independents.

According to caller polls, it volition apt travel down to a fewer Senate races that look to beryllium neck-and-neck, including successful the plaything authorities of Michigan.

The Republicans, meanwhile, are hoping to support their power of the House of Representatives. Currently, determination are 220 Republicans successful the House, compared with 212 Democrats — with much than a twelve races considered toss-ups.