Nick Smith the new Labour MP for Blaenau Gwent, said he was "delighted"
Labour have regained the south Wales valley stronghold of Blaenau Gwent, after previously losing the seat to an independent after a big party argument.
The party in Wales will be very relieved to have hung on in several seats targeted by the other parties.
But Cardiff North was lost by Julie Morgan to Tory Jonathan Evans by just 194 votes.
The Conservatives were also celebrating in the Vale of Glamorgan marginal, where Tory AM Alun Cairns won.
captured the previously Labour constituency
with a 4,300 majority.
However, across the south Wales valleys, along with Newport and Bridgend, Labour hung on to its seats.
After losing Cardiff North, Mrs Morgan said it had been a "great campaign" and Labour had put up a "really good show".
"It's under 200 votes and I feel it was a great showing for Labour in Cardiff. I'm committed to Cardiff and Labour.
Nick Smith, the new Labour MP for Blaenau Gwent, said after his victory: "I'm just delighted. It's a fantastic thing to happen." he said.
He added: "People in Blaenau Gwent wanted a strong voice in Parliament and I said I would stand up for them in parliament, and that's what I will do when I get up there.
"The local population and the Blaenau Gwent Labour Party have shared values and that's come through in this result tonight."
Carwyn Jones, Labour First Minister in the Welsh assembly, said: "I thought we would win Blaenau Gwent back. A lot of people have said Labour's power base in the valleys is being eroded - clearly that's not the case."