ผู้สมัครมีกี่ครั้ง Paul Tsongas (ง) 60.6% Paul W. cronin (r) 39.4%?ไม่จำเป็นต้องใช้ทุกตาราง
How many times was the candidates paul tsongas (d) 60.6% paul w. cronin (r) 39.4%?It is not neccessary to use all the tables.
 table_1341690_21:  (incumbent [ VARCHAR ] candidates [ VARCHAR) ]
SELECT COUNT(incumbent) FROM table_1341690_21 WHERE candidates = "Paul Tsongas (D) 60.6% Paul W. Cronin (R) 39.4%"