THERESA May has fired the starting pistol to the race to succeed her.

Boris Johnson is the bookies’ favourite but the favourite has rarely seized the Conservative crown and any contest throws up pitfalls and surprises.

If the ardent Brexiteer is to succeed, he will have to get through votes at Westminster among MPs and peers to make it to the final run-off between two candidates, who will take part in nationwide hustings before the grassroots membership.

The process, which begins in the week of June 10, will take several weeks. Many in the party believe it best if the new leader/PM is in place by the time Parliament rises for the summer recess in mid-July.

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The expected candidates in what has been dubbed the “Tory Grand National” include:

*Boris Johnson, 54, former Foreign Secretary, is favourite. Famously pulled out of contest to succeed David Cameron. Ebullient Old Etonian. Loved by English shire Tories but appeal lessens beyond Watford Gap. However, MPs' Stop Boris campaign could stop him making the final two-candidate stage.

*Jeremy Hunt, 52, Foreign Secretary, emollient Remainer turned Brexiteer, has carefully repositioned himself; last week made a pitch to Right Wing by proposing doubling of the defence budget over next decade.

*Michael Gove, 51, Environment Secretary, has been incredibly pro-active in his green brief. Articulate but not trusted by some colleagues following his “assassination” of Johnson’s chances last time round. Pro-Unionist Scot. Said to already have 50-60 backers.

*Dominic Raab, 45, former Brexit Secretary, who quit over May’s compromise approach, is pitching himself as a unity candidate, calling for income tax cuts and “fairer deal for working Britain”.

*Amber Rudd, 55, Work and Pensions Secretary, who quit as Home Secretary over Windrush scandal but was quickly rehabilitated. Leading Remainer, promoting herself as One Nation Tory. Achilles heel is 346 majority, which would make her target of Labour “decapitation” strategy at an election.

READ MORE: Theresa May resigns as Prime Minister 

*Andrea Leadsom, 56, Commons Leader, who dramatically bailed out of last contest following damaging newspaper interview, clearing way for May to succeed Cameron. Leading Leaver whose resignation this week began final push to get PM out.

*Sajid Javid, 49, Home Secretary, highly energetic son of bus driver. Hardened by experiences of dealing with Tata steel crisis and Grenfell disaster. Reluctant Remainer has already bagged £50,000 from supportive donors. Uninspiring public speaker but that did not stop Iain Duncan Smith from getting top job.

*Matt Hancock, 40, Health Secretary, a former aide to George Osborne at Treasury, Remainer and moderniser who has shot up through ranks and would be youngest contender. Spoken of “generational shift” needed post-May.

*Rory Stewart, 46, International Development Secretary, former diplomat and Black Watch officer. Thoughtful and softly spoken Remainer Scot but has no real block of MPs behind him.

*Penny Mordaunt, 46, new Defence Secretary, Royal Navy reservist and social liberal. Could be dark horse but is relatively untested. Famously appeared in reality TV show Splash!

*Liz Truss, 43, Treasury Chief Secretary, has arguably been most pro-active in shadow contest with Sunday paper photo-shoot and profile piece where she called for 1m homes to be built on Green Belt to help aspiring under-40s.

*Esther McVey, 51, former Work and Pensions Secretary, who again quit over May’s soft Brexit strategy. Keen Brexiteer, who launched her campaign this week under banner of Blue Collar Conservatism.

*Kit Malthouse, 52, Housing Minister and former Deputy Mayor of London, who was the architect of Malthouse Compromise to replace Irish backstop, which proposed so-called managed no-deal, attempting to bring Leavers and Remainers together.

*James Cleverley, 49, was Deputy Party Chairman and now Brexit Minister. Leaver is former Tory Leader in London Assembly. Rank outsider.