Carswell quit the party earlier in late March, and insurance broker Arron Banks responded by vowing to unseat the one-time Tory MP.
Banks has today confirmed that, following today's shock announcement from Theresa May, he will seek to win Carswell's seat of Clacton.
Asked on Twitter if he would stand in the June vote, Banks responded: "yes".
Carswell himself has yet to publicly respond to the election announcement, beyond highlighting a poll which suggests that just 59 per cent of Ukip's 2015 voters would back the party next time around.
One unknown, however, is former Ukip leader and Banks ally, Nigel Farage.
The MEP has yet to comment on May's early election plan, or whether he will launch another bid to win a seat in the House of Commons.