Southern Indiana Congressman Baron Hill has secured the Democratic nomination for his 9th District seat, setting up another rematch with Republican Mike SodrelHill and Sodrel will square off for the fourth time in a row this fall. Hill has won three of the contests. Sodrel unseated Hill in 2004 but Hill spoiled his re-election bid two years later.Baron Hill easily defeated three Democratic challengers in yesterday's primary. Sodrel was unopposed.In another congressional race, Democrat Andre Carson held off seven challengers to win his party's nomination in the 7th District, which includes Indianapolis. Carson won a special election earlier this year to serve the unexpired term of his late mother, Julia Carson.Longtime Republican Congressman Dan Burton also won his primary race in the state's 5th District.