Brendan Cox, whose wife was stabbed and shot by a right-wing extremist days before the EU referendum, said he welcomed a "robust debate" but urged people to give "short shrift to the haters".
The campaigner has planned a community event called the Great Get Together for June 16, the anniversary of his wife's death and just eight days after the election.
He said: "We've got a proud tradition of vigorous debate in this country.
"We can have strong opinions, big disagreements, but we can still respect those who take a different view.
"I welcome a robust debate, we should also give short shrift to the haters and drive them to margins where they belong.
"I hope we'll have an election that's respectful not divisive."
Mother-of-two Mrs Cox, 41, was shot and stabbed by neo-Nazi Thomas Mair outside Birstall Library, in her Batley and Spen constituency. He was later handed a whole-life prison sentence for her murder.
Her widower referenced a recent viral video showing Brenda from Bristol, who professed her weariness at having another election in a BBC News vox pop.
He said: "Brenda from Bristol captured the feelings of many when she told the BBC 'Not another one!'
"Brenda said there was 'too much politics'. I would say there is too much bitterness and hatred.
"We've seen it growing for a long time but it's not the British way."