Mississippi voters are deciding a racially charged mid-term election, that has dredged up the Deep South state's ugly past.
In the last Senate contest of the mid-term elections, white Republican Cindy Hyde-Smith faces an unexpectedly tough challenge by black Democrat Mike Espy.
The vote tightened after Ms Hyde-Smith was recorded telling a supporter she would happily attend a public hanging.
Nevertheless she is expected to win in the staunchly Republican state.
On Monday, several nooses were found at the Mississippi capitol in Jackson, in an apparent protest against the tenor of the campaign.
Signs alongside the ropes urged voters to elect "someone who respects the lives of lynch victims" and "remind people that times haven't changed", according to local media.
This election became more competitive after a video emerged earlier this month of Ms Hyde-Smith telling a supporter: "If he invited me to a public hanging, I'd be on the front row."
The senator's comment evoked the lynching of African-Americans in a state whose past is rife with racial violence.
According to the National Association for the Advancement of Colored People (NAACP), Mississippi had the highest number of lynchings in the nation from 1882 to 1968.
Mr Espy condemned his rival's comment as "reprehensible"; Ms Hyde-Smith maintained there was no "negative connotation".
The Democrat has himself come under scrutiny for his 2011 lobbying work in the Ivory Coast, whose former despot Laurent Gbagbo is on trial at the International Criminal Court.
Mr Espy was agriculture secretary under President Bill Clinton, but resigned under a cloud of corruption allegations, on which he was later acquitted.
Ms Hyde-Smith, meanwhile, was further criticised when photos surfaced of her posing at the home of Confederate President Jefferson Davis, with the caption: "Mississippi history at its best."
Donald Trump travelled to Mississippi on the eve of the vote to campaign for Ms Hyde-Smith.
He painted Mike Espy as a far-left ideologue who would "rather protect illegal aliens than people who live in Mississippi", and questioned how he "fit in with Mississippi".
Should he prevail, Mr Espy would become the first black senator since the Reconstruction era following the US Civil War.
His campaign has pushed the idea that electing Ms Hyde-Smith would stoke a lingering view of Mississippi as a racist southern state.
"We can't afford a senator who embarrasses us and reinforces the stereotypes we've worked so hard to overcome," one ad for the Democrat said.
Mr Espy would need to overwhelmingly win the black vote and a substantial number of white voters to unseat his Republican opponent.
After Republican Senator Thad Cochran resigned in April, a special election for Mississippi's US Senate seat was arranged.
Under the state's law, if no candidate wins over 50 percent of the votes, a runoff election must take place.
On 6 November during the mid-term elections, both Ms Hyde-Smith and Mr Espy received about 41 percent f the vote.
If Republicans hold on to the seat, their US Senate majority would be extended to 53-47.