Ann Coulter fears so:
For at least a century, there’s never been a period when a majority of immigrants weren’t Democrats. At the current accelerated rate of immigration — 1.1 million new immigrants every year — Republicans will be a fringe party in about a decade.
Michael Brendan Dougherty disputes this logic:
Although Coulter is right that immigrants have gravitated to the Democrats, the descendants of the 19th century great wave voted overwhelmingly for Nixon and Reagan. Many of them have come to view themselves as true conservatives, even if a century earlier America’s true conservatives wanted to ship their great grandparents back to Europe. … The relationship between the composition of the American people and the ideals adopted by the parties that seek to represent portions of them is complex. We cannot predict how the addition of new immigrants will pressure and cleave the Democratic coalition. But, in general, our two political parties have accumulated so much inherited power, including the power to change, that it is difficult to imagine either of them ever being mortally wounded.
The Dish 