Contenders to replace British Prime Minister Boris Johnson were racing Tuesday to clear their first hurdle amassing enough support from colleagues to make the Conservative Party leadership ballot. Nominations officially opened Tuesday morning and will close at 6 p.m. (1700GMT). Candidates need support from at least 20 Conservative lawmakers to be on the ballot for run-off votes, which will start Wednesday. So far only three of the 11 declared candidates have met the threshold: former Treasury chief Rishi Sunak, Trade Minister Penny Mordaunt and backbench lawmaker Tom Tugendhat. Several others are likely also to reach the mark, including Foreign Secretary Liz Truss, Treasury chief Nadhim Zahawi and former Health Secretary Jeremy Hunt. The candidates are jostling to replace Johnson, who quit as Conservative leader last week amid a party revolt triggered by months of ethics scandals. He will remain in office as a caretaker prime minister until his replacement as party chief is chosen. The winner of that contest will automatically become prime minister, without the need for a national election. The new leader will be chosen in a two-stage election, in which the 358 Conservative lawmakers reduce the race to two candidates through a series of elimination votes. The final pair will be put to a ballot of party members across the country. The party aims to complete the parliamentary stage of the election before lawmakers break for the summer on July 21. The two final candidates will then spend the summer campaigning around the country. The new leader is due to be announced when the House of Commons returns on Sept. 5. Many Conservatives are wary of leaving Johnson in office for too long, concerned a lame-duck leader is the last thing Britain needs with war raging in Ukraine, food and energy price increases driving inflation to levels not seen in decades, and growing labor unrest. Some also worry Johnson — brought down by scandals over money, rule-breaking and his handling of sexual misconduct allegations against lawmakers — could do mischief even as a caretaker prime minister. The opposition Labour Party says it will push to hold a no-confidence vote in Johnson in the House of Commons this week. But it is unlikely to gain enough Conservative support to pass, as many Tories resist voting with the opposition even against a tarnished leader. In the wide-open leadership contest, contenders are striving to set themselves apart from the perceived front-runner Sunak, who already has the backing of more than three dozen lawmakers. Many have repudiated the tax increases Sunak introduced to shore up U.K. finances battered by the coronavirus pandemic and Brexit — a 1.25% income-tax rise for millions of workers, and an increase in corporation tax next year from 19% to 25%. Most candidates say they will scrap one or both. Sunak, whose resignation a week ago helped topple Johnson, has cast himself as the candidate of fiscal probity, and warned rivals not to tell the public "comforting fairy tales." Zahawi hit back that his own tax-cutting plan was "fully costed." "I believe cutting taxes isn't a fairy tale, but rather a critical step to tackle the cost-of-living crisis," he said. — Agencies