CONCORD, N.C. — Martin Truex Jr. led a Sprint Cup-record 588 of 600 miles to win the Coca-Cola 600 on Sunday night, racing away from his bad-luck past at NASCAR’s longest race. Truex Jr. started from the pole, moved quickly out front and led all but eight of 400 laps for his first win in 34 events since June 2015 at Pocono Raceway. Truex ran strong enough the past year to grab a bunch more checkered flags, but something always went awry.