Liberal Democrat leader Nick Clegg's 'change' plea

Nick Clegg hit the campaign trail with his wife Miriam Gonzalez Durantez

Liberal Democrat leader Nick Clegg has told an audience in Newport the election offered a "once in a generation opportunity" for change.

Mr Clegg, visiting the Riverfront theatre and arts centre, asked people to vote with their hearts.

On the final weekend of the campaign, Labour's Harriet Harman and Lord Adonis were also in Wales to canvass support.

The Conservatives' Caroline Spelman was in Powys while Plaid Cymru marked 44 years since gaining their first MP.

Fresh from the final TV prime ministerial debate, Mr Clegg made his third trip of the 2010 election campaign to Wales when he accompanied his party's candidate on a visit in Newport East on Saturday.

He told his audience: "Don't let anyone tell you that somehow your vote doesn't count.

Tory Cardiff North candidate Jonathan Evans (right) met voters on Saturday

"Don't let anyone tell you that they want to lend your vote in this direction or tactically vote in that direction.

"No, this time we have a once in a generation opportunity to change things for good, and so this time vote with your heart."

Plaid Cymru supporters gathered in the centre of Carmarthen to celebrate 44 years since the party's first MP, Gwynfor Evans, was returned to Westminster.

Plaid pointed to their "MPs' track record and achievements" and emphasised "the difference that even more Plaid MPs at Westminster could make as the prospect of a balanced parliament becomes more and more likely".

'Major concessions'

The party's candidates in the area, Jonathan Edwards in Carmarthen East and Dinefwr and John Dixon in Carmarthen West and South Pembrokeshire, said Plaid had a track record of delivering for Wales.

Mr Edwards said: "Plaid MPs led opposition to the illegal war in Iraq, have led calls for compensation for miners, steelworkers and quarry workers and were instrumental in setting up S4C.

"Plaid Cymru MPs have won major concessions for the Welsh language, as well as improving the rights of children and the disabled."

Labour's Harriet Harman was campaigning on family issues

Labour Deputy Leader Harriet Harman was campaigning alongside her party candidates Jess Morden, Julie Morgan and Nia Griffith - in Newport, Cardiff North and Llanelli - on the party's record in supporting families.

'Extremely close'

Ms Harman said a Conservative victory in the election would be a "disaster for families across Wales".

"We cannot let David Cameron enter Downing Street through the back door," she said.

"This election is extremely close and we need everyone to come out and vote Labour to keep the Tories from wrecking Wales."

Transport Secretary Lord Adonis was due to visit Wrexham train station to meet local rail user groups.

Conservative shadow Communities and Local Government Secretary Caroline Spelman was canvassing in Hay-on-Wye where she joined the party's local candidate, Suzy Davies.

Plaid Cymru were in Carmarthen to rally support

'Vitally important'

Ms Spelman spoke to organisers of the annual Hay Festival before meeting voters during a walkabout in the town.

A party spokesman said the festival was "vitally important" to the local economy and had given the area an international profile.

Conservative supporters were also out and about in Cardiff North where their candidate Jonathan Evans was canvassing.

Meanwhile a poll carried out for the Western Mail newspaper among voters in Wales puts Labour on 37.5%, the Conservatives on 23.5%, the Liberal Democrats on 21% and Plaid Cymru on 10.8%.

It also puts UKIP on 2.4%, the Greens on 1% and others on 3.7%.

Cardiff-based Research and Marketing Plus interviewed 1,000 voters across Wales by telephone between 26 and 29 April.