The Conservative leadership race is now officially underway with eight candidates making the ballot.

Voting gets underway later today and we’ll get a sense of the levels of support the candidates have at 5pm when the results are announced. To progress to the next round, candidates will need to secure a minimum of 30 votes.

Over the next week and a half, Conservative MPs will be attending hustings with the leadership candidates and voting for the two to put to the wider membership.

Leadership elections are often unpredictable; this one particularly so, considering the large size of the field and the fact that there is no stand out favourite.

The Parliamentary stages of the Tory leadership are the ultimate in backroom dealmaking. What are the terms on which prominent MPs make public declarations for a candidate? What happens when a candidate throws in the towel or is eliminated – to whom do they offer support?  What possibilities of the secret ballot will be exploited where MPs pledge for more than one candidate?

In 2001, Michael Portillo was so convinced he had the numbers of MPs sown up to progress to the final round that he focussed his attention on campaigning to the membership and ended up losing the last Parliamentary vote. It’s been suggested he was so wrong-footed he didn’t feel the need to vote for himself – particularly awkward given he lost by one vote.

This time around, it appears that Rishi Sunak could well make the final cut but polls suggest he’ll struggle with the membership. He’s pivoting his campaign already towards the grassroots. The others are taking it one step at a time and focussing their attention on fellow Conservative MPs.

The different Conservative factions will be crucial. They are more complicated than they used to be; no longer just the Wets (left wing) and Dries (right wing) but instead a large number of caucuses, most will host husting meetings throughout the campaign.

Blue Collar Conservatives – 160-strong group with a belief in a practical conservatism to support working people. In a different time, Boris Johnson was a hero to the group and they credit themselves with breaking down Labour’s ‘Red Wall’ in the north of England.

Common Sense Group – 30 MPs on the right of the parties. Concerned with culture war issues and what its chair, the Tory backbencher John Hayes, terms a struggle against “subversives” such as Black Lives Matter and Extinction Rebellion, its 136-page policy booklet sets out ideas on everything from immigration to the legal system and family life.

Tory Reform Group – 110  MPs on the political left of the party. Formerly more in favour of remaining in the European Union.

Conservative Environment Network – 130 MPs that are concerned about the natural environment and support the green agenda

Northern Research Group 50 MPs led by the former Northern Powerhouse minister Jake Berry, this is a geographical faction aimed at boosting spending and investment in the north of England, north Wales and Scottish borders.

Covid Recovery Group 60 MPs led by the former chief whip Mark Harper and the former Brexit minister Steve Baker, the CRG’s size and opposition to new Covid rules is essentially the reason why England had notably fewer restrictions than other UK nations

Some of the groups will end up publicly supporting a particular candidate and others won’t, but these groups will be crucial through the campaign as front runners emerge and tactical voting takes place to stop particular candidates from progressing.