George Galloway says The Workers Party is in a position to “radically alter” the course of the next general election.
The 69-year-old shocked Westminster last month when he romped to victory in the Rochdale by-election.
Galloway’s return to Parliament was made notable by Labour and Conservative failures, with neither party even making the top two.
Labour had stood down its candidate Azhar Ali over comments he made about Israel and Jewish people.
George Galloway spoke out on his by-election success on GB News
POOL / GB NEWS
But he was still listed as the Labour candidate on the ballot paper as the decision was made too late in the day for another candidate to take his place.
His expulsion paved the way for a comfortable Galloway victory, and the controversial figure has vowed to heap more misery on Sir Keir Starmer.
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“This was the straw that broke the camel’s back in Rochdale”, he told Neil Oliver on GB News.
“The spread of candidates, challengers, new parties, independent candidates and so on is now proceeding like wildfire.
“If I tell you that I have now in my pocket more than 300 prospective Parliamentary candidates all paying their own election expenses, imagine that.
“We didn’t have three, four weeks ago. Now we have 300. We are talking about a challenge to the legacy parties in practically every constituency in the land, certainly many hundreds.
Neil Oliver was joined by George Galloway on GB News
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Starmer insists his party would have won if it didn't have to stand down Azhar Ali
PA“And thus, the course of the next general election is radically altered.
“We will either win seats, or we will stop Sir Keir Starmer winning them. All bets ar off.”
Following Galloway’s comprehensive win in Rochdale, Starmer insisted his party would have won if they had a candidate standing officially.
The Labour leader vowed to field a “first-class candidate” in the general election., likely to be this autumn, in the Greater Manchester constituency.
Their expelled candidate, Ali, ended up coming fourth.
Starmer told MPs last month: "Galloway only won because Labour didn't stand a candidate.
"I regret that we had to withdraw our candidate, I apologise to voters in Rochdale, but I took that decision - it was the right decision - and when I say I've changed the Labour Party, I mean it.
"Obviously, we will put a first class candidate, a unifier before the voters in Rochdale at the general election."