The House of Commons on Tuesday approved the December 12 election in the hope of breaking the deadlock over Britain's departure from the European Union. Johnson's Conservative Party has a wide lead in opinion polls.
Britain's political leaders tested their election pitches on Wednesday after parliament backed Prime Minister Boris Johnson's bid for a pre-Christmas poll aimed at breaking the lengthy Brexit deadlock.
Lawmakers late Tuesday put aside their disputes and overwhelmingly supported Johnson's call for a snap general election on December 12.
The decision came two days before Britain was due to leave the European Union after 46 years and a few hours after Brussels granted London more time to secure parliamentary backing.
Parliament now has up to January 31 to lend their support to Johnson's divorce deal so that Britain can move past its biggest political crises since World War II.
But European Council chief Donald Tusk has warned the bloc's other 27 members may not grant Britain more time – similar words to those issued before the last extension in April.
Party leaders wasted no time in rolling out their messages even before the launch of their parties' official manifestos.
Johnson immediately rallied his parliament members after the vote with a promise to "get Brexit done", while conceding he was in for a hard fight.
The Conservative leader heads a minority government, which has hindered his ability to push through legislation in parliament. He is now hoping to turn that into a majority.
"It'll be a tough election and we are going to do the best we can," he said.
'Let the people decide'
Britain's first December vote in nearly 100 years and third general election in four years finds the main opposition Labour Party splintered by bitter infighting.
Pro-EU supporters from big cities have been at loggerheads with Brexit-backing groups such as trade unions as well as party leader Jeremy Corbyn.
But the veteran socialist is an energetic campaigner who nearly managed to secure an upset victory in the last general election in 2017.
Corbyn calls the vote "a once-in-a-generation chance to transform our country" and is promising "the most ambitious and radical campaign for real change".
His deputy and finance spokesman John McDonnell hailed his boss's abilities on the stump.
"I think we'll have a majority government by Christmas, so I can't think of a better Christmas present," he told BBC radio on Wednesday.
Labour's Brexit promise is to seize power and then strike a more European-friendly agreement with Brussels that preserves many of the existing trade ties.
It would then let voters choose between that deal and the option of simply staying in the EU.
"We're saying – democracy, let the people decide," McDonnell said.
The two other main players are adopting much firmer Brexit stances.
The fast-rising Liberal Democrats are going into the vote on a simple promise of stopping the EU-UK divorce by any means.
The party used a similar message to finish a surprising second in the European Parliament elections in May.
A poll of polls compiled by Britain Elects put them in third place with 18 percent of the vote. The Conservatives led second-place Labour by 35 to 25 percent.
A similar outcome could turn the Liberal Democrats into power brokers who decide the makeup and direction of the new government.
But party leader Jo Swinson said her polling showed the party was "within a small swing" of winning "hundreds of seats".
"I can't be clearer. Neither Boris Johnson nor Corbyn is fit to be prime minister," Swinson told BBC radio.
"Our country deserves a better choice, and I am standing as candidate to be prime minister."
The Brexit party of anti-European populist Nigel Farage stands on the opposite end of the political spectrum and holds fourth place on 11 percent.
Farage was one of the Brexit campaign's figureheads who won the May European poll within months of forming his new group.
But his party's impact has been muted by Johnson's own firm pro-Brexit message. Farage is now denouncing Johnson's agreement with Brussels as a sellout of Brexit interests.