Boris Johnson and his former finance minister Rishi Sunak were leading potential contenders to replace British Prime Minister Liz Truss on Friday, with candidates canvassing support to become Conservative Party leader in a fast-tracked contest.
Truss, chosen by party members to succeed Johnson after he was ousted by his lawmakers in July, quit herself on Thursday after six turbulent weeks in power.
Those who want to replace her must secure 100 nominations from Conservative lawmakers by Monday to run in a contest that the party hopes will reset its ailing fortunes.
With opinion polls suggesting the Conservatives would be all but wiped out if a national election were held now, the race is on to become the fifth British premiere in six years. An election is not due to be held for two years.
The winner will be announced on Monday or next Friday.
In what would be an extraordinary comeback, Johnson, who remains popular with party members was being touted alongside Sunak as a likely candidate.
"He can turn it around again. And I'm sure my colleagues hear that message loud and clear," Conservative lawmaker Paul Bristow told LBC radio. "Boris Johnson can win the next general election."
But Johnson, who left office comparing himself to a Roman dictator twice brought into power to fight crises, might not reach the 100 nomination threshold after his three-year premiership was blighted by scandals and allegations of misconduct.
The Financial Times said a Boris comeback would be "farcical".
One of his former advisers, who no longer speaks to Johnson and requested not to be identified, said he was unlikely to reach the target, having alienated dozens of Conservative lawmakers.
Will Walden, who also once worked for Johnson, said the former leader was returning from holiday and taking soundings.
Business minister Jacob Rees-Mogg tweeted his support, using the hashtag "#Borisorbust".
Defence Secretary Ben Wallace ruled himself out of the running and said he was leaning towards backing Johnson, who led the party to a large majority at a 2019 national election.
Sunak, the former Goldman Sachs analyst who became finance minister just as the COVID-19 pandemic arrived in Europe and was runner-up to Truss in the summer's leadership contest, is the favourite with bookmakers, followed by Johnson.
Third-placed is Penny Mordaunt, a former defence minister popular with party members who came third last time. None have formally declared their candidacy.
A Reuters tally of Conservative lawmakers who have made public declarations of support put Sunak on 54 backers, Johnson on 29 and Mordaunt on 16.
Britain's shortest-serving prime minister, Truss quit after her economic plans were rejected by investors, hitting the pound and pushing up borrowing costs, forcing a U-turn under a new finance minister after she sacked her closest political ally.
The sight on Thursday of yet another unpopular prime minister making a resignation speech in Downing Street - and the start of a new leadership race - underscored how volatile British politics has become since the 2016 Brexit vote.
Luxembourg's Prime Minister Xavier Bettel said Brexit had brought instability to Britain.
"I hope that they will soon be stable because even if they are not a family member anymore they are a friend and a neighbour. We need them and they need us too," he told reporters on arrival for an EU summit in Brussels.
The Conservative Party has a big majority in parliament and can ignore calls for an election, but opposition parties, some newspapers and even a few of its own lawmakers have said voters should now be given a say.
"The Tories (Conservatives) cannot respond to their latest shambles by yet again simply clicking their fingers and shuffling the people at the top without the consent of the British people," Labour Party leader Keir Starmer said.
"They do not have a mandate to put the country through yet another experiment."
Some Conservative lawmakers have urged colleagues to coalesce around one candidate to minimise the bruising.
Sunak, who had warned that Truss's fiscal plan threatened the economy, remains unpopular with some party members after he helped to trigger the rebellion against Johnson.
Mordaunt is seen as a fresh face, largely untainted by earlier administrations but also untested.
The next leader will inherit an economy heading for recession, with rising interest rates and inflation over 10% leaving millions facing a cost-of-living squeeze.
Surveys on Friday showed British shoppers have reined in their spending sharply and put their confidence levels near record lows, while worse-than-expected public borrowing figures underscored the economic challenges ahead.
Truss's spokeswoman said work was continuing on a fiscal plan due to be set out on Oct. 31 but that it would be for her successor to decide whether to proceed with it.
Whoever takes over also has a mountain to climb to restore the party's own reputation.
"Whether or not a change of leader is going to be sufficient to make the Conservatives actually electorally credible is certainly highly debatable," political scientist John Curtice told LBC.