Take a gander:
Until the 1970s, the majority of persons naturalizing were born in European countries. The regional origin of new citizens shifted from Europe to Asia due to increased legal immigration from Asian countries, the arrival of Indochinese refugees in the 1970s, and the historically higher naturalization rate of Asian immigrants. Consequently, Asia has been the leading region of origin of new citizens in most years since 1976.
Thirty-six percent of persons naturalizing in 2011 were born in Asia, followed by 31 percent from North America, and 12 percent from Europe (see Table 1). Mexico was the leading country of birth of persons naturalizing in 2011 (14 percent). The next leading countries of origin of new citizens in 2011 were India (6.6 percent), the Philippines (6.1 percent), the People’s Republic of China (4.7 percent), and Colombia (3.3 percent).
So why don't politicians care about the Asian voting bloc?