The UK's most marginal seat was held by the Conservatives due to Jeremy Corbyn and Brexit, according to its MP.
Southampton Itchen was previously held by Royston Smith with a majority of just 31 votes in 2017.
Today Mr Smith increased his majority to 4,498 votes, beating Labour's candidate Simon Letts.
The MP said the Labour Party leader and his position on Brexit aided his win.
He added: "I will try to improve our infrastructure, quality of jobs, better education, more money for our hospital and schools.
"Hopefully over the next five years you’ll see some good improvements.”