Plaid Cymru

Plaid Cymru emerged from the 2005 general election with somewhat disappointing results. It lost the Ceredigion seat to the Liberal Democrats and saw its overall representation fall to three points, its lowest level since 1992. Its share of the vote was also down, leaving the party with just 12.6%.

But things change. In 2006, the party underwent a comprehensive image upgrade, with its green and red branding replaced by bright yellow, and the 'triban' logo, used since 1933, changed to a yellow poppy. Constitutional changes finally gave the party's assembly leader the role of overall leader.

In the 2007 Assembly elections in 2007 Plaid increased its number of seats from 12 to 15 and, after much negotiation and constitutional wrangling, became junior partner in a Labour-led administration. That deal meant Labour was committed to pushing for a yes vote on a referendum for full law-making powers for the Assembly. Ieuan Wyn Jones was made deputy first minister, as well as holding the economy and transport briefs.

In December 2009 the party was hit by Mohammad Asghar's decision to defect to the Tories. As the first ethnic minority and Muslim member of the Assembly, his switch of allegiance hit the party hard.

Plaid hopes to increase its number of MPs from three to five at the general election. That's complicated somewhat by the fact boundary changes are about to reduce their number of MPs to two. Interestingly, the party's main battles, while small in number, incorporate the full spectrum of Westminster politics: they are fighting very different campaigns against Labour, the Lib Dems and the Tories. The best possible option for the party would be to return seven MPs. That's the number of seats they hold at constituency level at the Welsh Assembly, and optimistic strategists think there's no reason they shouldn't be able to replicate that at a Westminster election.

But things aren't always so simple. Plaid voters are more likely to turn up at Assembly election, in part to prove the legitimacy of devolution. They also feel Plaid has a better chance of being in government at an Assembly level - not least of all because they are. On a UK level that seems less likely. But campaigners argues the possibility of a hung parliament means Plaid could in fact have a highly influential role - and they've proved their maturity when it comes to coalitions via their role in the Assembly.