Caerphilly By-Election: Reform 2/5 to beat 2/1 Plaid Cymru and 59/1 Labour

• Reform favourites to end Labour dominance in Caerphilly

• Market says only Plaid Cymru can stop Farage's party 

• By-election result will give clues to parties' standings nationally

• Get the latest Betfair Exchange odds for Caerphilly by-election

Caerphilly by-election is Reform v Plaid Cymru with Labour 59/1

Reform UK will win their first seat in the Welsh parliament in today's Caerphilly by-election, according to the latest odds on the Betfair Exchange on Thursday morning.

Voting is underway in the south Wales constituency and politicians in Cardiff and Westminster will have their eye on the outcome.

As it stands at 11am on Thursday, Reform UK are 1.42/5 (a 71% chance) to win the by-election. 

Their nearest rivals in the betting are Plaid Cymru at 3.02/1 (33%). 

South Wales has been a stronghold for Labour this century. They won the seat at the last Senedd election but, at 60.059/1 to win the by-election today, it would be a shock if they were to hold the seat.

The sudden death of the area's Member of the Senedd, Labour's Hefin David, in August is the reason for today's by-election. David was first elected in 2016, and Labour have held the seat since devolution began in Wales in 1999.

Losing today would add to Labour's difficulties in the Senedd where they currently hold 30 of the 60 seats. Defeat in Caerphilly would make Labour even more reliant on other parties to pass legislation.

The result of the by-election is a potential bellwether for next May's national Senedd elections.

Farage fav to be next PM as Reform target Caerphilly win

For Reform, winning a first seat in Wales would be a further indication that they are on course to challenge at the next UK general election. 

Nigel Farage is 4.84/1 favourite to be the UK's next prime minister while Reform are 1.9310/11 to win the most seats with Labour 3.55/2. 

The UK general election isn't scheduled to take place until 2029 - although the prime minister has the option to call it before then - and, in the meantime, there will be Welsh elections next year.

A victory for Reform would send a message that they can make in roads at the Senedd in 2026 and shake up its make-up in the same way they are hoping to do in Westminster. 

The result is expected in the early hours of Friday 24 October.

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