TDS founding co-editor Stanley Ggreenberg has an article up at Financial Times, discussing how “Immigration exposes political weakness.” Noting that, after their 2012 shellacking, many Republicans suddenly saw the light and became supporters of “immigration reform that included a path to full US citizenship,” Greenberg explains:

This repositioning will not be pretty. In the past few decades, citizens in developed countries have often demanded that governments take control of borders in response to globalisation. Many feel their concerns have been ignored – or, worse, dismissed as ignorant or even racist. They feel let down by politicians on the left and the right. Nevertheless, conservatives have until recently benefited from scepticism about the gains from immigration; this is now changing, across the rich world.
Mr Romney knew what he was doing when he used immigration to define himself as an authentic and “severe” conservative. He played to the anger and frustration of Republican voters. It helped him win over a sceptical party and to win the primary. But later, it also helped him to lose the election.
Now, Republican leaders will probably not block immigration reform because of the electoral mathematics. Business support for reform is also important. The US Chamber of Commerce, and industrial, agricultural, and high-tech sectors are desperate for reform to meet their needs. A battle has begun between the political and corporate elite and the Republican base.

Greenberg sees a similar “problem for the political right” across Europe, where “conservative politicians are caught primarily between extremists and nativist sentiment to their right and more liberal voices to their left” and adds,

This confusion has made immigration an explosive issue. It was at least as important as public spending when British voters threw out Gordon Brown in 2010, who dismissed a voter who quizzed him about eastern European migrants as “bigoted” during his ill-fated campaign. Immigration today is the first or second priority for citizens across Europe, according to polls.
Under Tony Blair, Britain introduced restrictions on asylum seekers and adopted a points system for non-EU migrants. These changes were rendered irrelevant, however, in the eyes of many voters when eastern European immigration exceeded estimates by a factor of 20.
More recently, David Cameron’s Conservative party lost disastrously to the United Kingdom Independence party in the Eastleigh by-election, in large part because of worries about immigration. Mr Cameron has promised to make life tough for the Romanians and Bulgarians who might come when they are permitted to work in the UK next year, and to tighten benefit rules, but this has not stemmed the Tory erosion. They lead the opposition Labour party by only three points on the issue of immigration – and trail Ukip by 13.

Greenberg cites an electoral victory by conservative Alfred Gusenbauer in Austria, when he “moved ahead of other Social Democrats and spoke comfortably about immigrants learning German and their families respecting women’s rights” and became chancellor. Greenberg adds that the lesson has not been lost on the UK’s Labor Party leader Ed Miliband, “who has made repeated efforts to position himself wisely on immigration.”
Here in the U.S., however, it remains to be seen whether Republicans are ready to give up the nativist pandering to the satisfaction of Latino voters, many of whom have problems with GOP economic policies. Democrats, meanwhile, have staked out both economic and immigration policies that should keep them in good stead with this key constituency.