And while his Conservative government command healthly majorities in Ms Dorries’ Mid Bedfordshire and Mr Adams’ Selby and Ainsty constituencies, the situation is far more precarious in the former prime minister’s seat of Uxbridge and South Ruislip.
Despite leading his party to an 80-seat majority in 2019 with the “Get Brexit Done” slogan, Mr Johnson - who blamed his departure on a “witch hunt” over the Partygate scandal - only won his seat by 7,210 votes.
How far, if at all, this poll lead will eat into support for the Tories in Ms Dorries’ and Mr Adams’ true-blue constituency - where they both won by more than 20,000 votes in 2019 - remains to be seen.
And after Mr Johnson said he was leaving parliament “at least for now”, it has even been speculated that he could return to stand as a candidate in his former culture secretary’s old seat.
As both MPs launched blistering attacks on Mr Sunak’s government, The Independent has taken a look at how the Tories’ odds fair in the looming polls.
Boris Johnson - Uxbridge and South Ruislip
Uxbridge and South Ruislip has been held by Mr Johnson since May 2015 and the Conservative Party since its creation in 2010. Before this, its predecessors - Uxbridge and Ruislip-Northwood - had been held by the Tories for decades.
In the 2019 Conservative landslide, the then-prime minister held the seat by winning 25,351 votes. This gave him a majority of 7,210 based on a 68.5% on an electorate of 70,365.
Mr Johnson’s majority was relatively modest compared with some ultra-safe Tory and Labour seats where MPs can command majorities of over 20,000 votes.
In the 2019 poll, Labour - led by Jeremy Corbyn - won 18,141 votes, equating to 37.6% of the turnout, through its candidate Ali Milani.
Liberal Democrat candidate Joanne Humphreys was in third with 3,026 (6.3%) votes, while Mark Keir came fourth for the Greens with 1,090 (2.3%) ballots cast in his favour.
Labour has already selected Camden councillor Danny Beales to represent it in the ward in the upcoming poll.
Shabana Mahmood, Labour’s campaign coordinator, told Sky News: “Boris Johnson’s handling of the last 24 hours speaks for itself. This is not a man who is about anything other than Boris Johnson and frankly, the sooner everybody stops giving him limelight and attention that he clearly craves the better.
“What we care about is the voters of Uxbridge, he has shown disdain for the voters of Uxbridge, but Danny Beales as a Labour candidate and future MP for Uxbridge will put the people of Uxbridge first, he will be fighting for them in Parliament, that’s what the people here need and that is singularly what Boris Johnson has always failed to do.”
Despite this, recent polling by former Tory donor Lord Ashcroft predicted that Mr Johnson would win a byelection.
Writing on his blog on Thursday, he speculated on the likelihood of a poll being held if Mr Johnson was suspended after being found to have misled parliament over the Partygate scandal, a byelection was called and he decided to stand in it for the Conservatives.
He said: “Our survey of the Uxbridge & South Ruislip seat completed on Friday suggests he would win a by-election tomorrow with 50% of the vote, with Labour’s Danny Beales on 33% and Liberal Democrat Blaise Baquiche a distant third on 6%, a single point ahead of the Greens.”
Bookies Ladbrokes currently have Labour as 1/10 favourites to win the constituency, with the Conservatives in second place on 6/1.
Alex Apati, from the firm, said "the odds suggest it would take nothing short of a miracle at this point for Labour not to win the upcoming” poll.
Nadine Dorries - Mid Bedfordshire
Ms Dorries has always enjoyed a significant majority since she was elected in 2005, winning it by 24,664 votes at the last general election.
This mammoth lead saw her earn nearly 60% of the vote - almost tripling the percentage of the turnout won by Labour candidate Rhiannon Meades (21.7%) when she had 14,028 ballots cast in her favour in 2019.
The Lib Dems were a distant third with 8,171 (12.6%), while the Greens lagged even further behind on 3.8% of the turnout with 2,478 votes.
Prior to her tenure, the seat - and its various guises - have returned Conservative MPs exclusively since 1931.
Despite this mountain to climb, Labour went on the offensive this morning - claiming that only it can win the seat.
Rachel Hopkins - an MP for the nearby constituency of Luton South - shared a polling graph which claimed her party was only two points behind the Conservatives in the area and therefore voting for the Liberal Democrats would make no sense.
She wrote: “Labour is the only party that could beat the Conservatives in #MidBeds”
And writing on its Facebook page, Mid Beds Labour said: “Ours is a wonderful constituency, but Nadine Dorries has not 'served' us or even been present at all.
“It’s time for a Labour MP who will care about the people of Mid Beds, defend our public services, especially our NHS and schools, and listen to local communities.”
A piece on The Polling Report claimed that “even with the current state of polling, based on a Uniform National Swing, it looks like it could well stay in Tory hands”.
This is down to tactical voting placing a large part in recent byelections oustings, it said. However, this is not so “clear cut” in Mid Bedfordshire which made lead to the opposition vote being split.
It went on to say that while a Conservative loss “is more than possible, it may well depend on how well opposition parties can co-operate”.
Nigel Adams - Selby and Ainsty
Known as the former prime minister’s “Mr Fixit”, Mr Adams has represented the constituency in the Yorkshire and The Humber since 2010.
Over the decade’s ensuing elections, the staunch Johnson loyalist and former party whip returned solid majorities over 10,000 and he appeared to enjoy bumper support during the 2019 election - as much of Labour’s Red Wall fell to the Tories.
In its previous guise - when it was simply called Selby - the seat went the way of the governing party at every election from its creation in 1983.
This saw it remain a Labour marginal throughout the Blair and Brown years - with their majority gradually cut to less than 500 votes by the 2005 election before it was flipped in 2010.
Now that the Tories’ majority has grown to 20,137 it represents a significant challenge for Labour to overturn.
But as the news broke, the constituency’s branch appeared to be ready to contest the poll.
Matt Burton, its secretary, tweeted: “Bring on the by-election.”
Whether Sir Keir’ party realises its ambition remains to be seen.
Website Polling Report predicted that the Conservatives would win a by-election - although they would lose about 15% of their vote - the majority of which would go to Labour.
It believes that the Liberal Democrats would be in third with around 8% and the Green in fourth on 6%.