Democratic presidential front-runner Barack Obama announced Saturday he had resigned his 20 year membership in the Trinity United Church of Christ in Chicago in the aftermath of inflammatory remarks by his longtime pastor, the Rev. Jeremiah Wright, and more recent fiery remarks at the church by another minister. In so doing, Obama sought to fend off further criticism and solidify his position ahead of an expected general election race against likely Republican nominee John McCain. "This is not a decision I come to lightly ... and it is one I make with some sadness," he said at a news conference in South Dakota after campaign officials released a letter of resignation sent to the church on Friday. Comments by Wright had inflamed racial tensions and posed an unwanted problem for Obama as he seeks to wrap up the nomination.