How will a Post White America Republican Party stand in elections?

Let's face it, rightly or wrongly the republicans are seen as the white mans party by the majority of voters. When white people are a demographic minority in 20 years how do the Republicans expect to win elections? Minorities will no longer need you since they can form their own political parties and have the demographic edge in elections. Will white conservatives become an insignificant voting bloc or will they relocate to certain states and still retain some political control in key areas? How do you see the Republican party in 20 years time?