CREATE TABLE table_53434 ("Date" TEXT, "Visitor" TEXT, "Score" TEXT, "Home" TEXT, "Leading scorer" TEXT, "Attendance" FLOAT, "Record" TEXT)

How many people were in attendance when the visiting team was the Nuggets and the leading scorer was J.R. Smith (28)?
SELECT SUM("Attendance") FROM table_53434 WHERE "Visitor" = 'nuggets' AND "Leading scorer" = 'j.r. smith (28)'
SELECT SUM("Attendance") FROM "table_53434" WHERE "Leading scorer" = 'j.r. smith (28)' AND "Visitor" = 'nuggets'