WATCH: ITV Anglia's Political Correspondent Emma Hutchinson rounds up the day's politics from Luton.
The leader of the Liberal Democrats said her party's economic policies are "robust" and "costed" in a visit to the St Albans constituency.
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Before her speech, Ms Swinson visited St Albans, which is her party's foremost target in the Anglia region.
It is currently held by the Conservatives, but a majority of 6,109 means the Lib Dems would need a swing of just 5.4% to take the seat.
During her visit, Ms Swinson looked round Imagination Technologies - a technology company based in King's Langley.
"We’re the party that’s setting out robust, economic plans - a costed manifesto rather than the shopping list that isn’t funded that you get from the other parties now.
St Albans constituency candidates:
Anne Main, Conservative
Daisy Cooper, Liberal Democrat
Simon Grover, Green
Rebecca Lury, Labour
Jo Swinson, Liberal Democrat leader
Labour in Luton
Elsewhere on Monday, Labour's Shadow Police Minister Louise Haigh visited Luton.
She was there to support local candidates and hold a round-table discussion on crime and policing.
Luton North candidates:
Jeet Bains - Conservative
Simon Hall - Green Party
Linda Jack - Liberal Democrats
Serena Laidley - Women's Equality Party
Sarah Owen - Labour
Sudhir Sharma - Brexit Party
Muhammad Yasin Rehman - Independent
Luton South candidates:
Parvez Akhtar - Conservative
Mohammed Ashraf - Independent
Ben Foley - Green Party
John French - Best4Luton
Rachel Hopkins - Labour
Gavin Shuker - Independent
Garry Warren - Brexit Party