Bernie Sanders interrupted a press conference to rush to a man who fainted at the event.
The Democratic party presidential candidate was speaking in New Hampshire when a man watching from the sidelines was heard falling to the floor.
The self-described “democratic socialist” senator from Vermont stopped mid-sentence and was heard to say “oh my God”.
He then added: “Can we have a physician in.”
The man was seen lying on the floor for a short while before being helped to walk out of the room, after receiving a pat on the back from Mr Sanders.
The senator very narrowly lost the Democratic party’s Iowa caucus on Monday, with Hilary Clinton winning 49.9 per cent of the electorate’s votes – to Mr Sanders’ 49.6 per cent.