Complex sentence: Istook received $29,000 in campaign contributions from Abramoff and some of his clients, and wrote letters urging the Bush administration to reject a casino proposal that Abramoff's clients opposed.
Split into simpler sentences: Istook received $29,000 in campaign contributions from Abramoff and some of his clients. Istook wrote letters urging the Bush administration to reject a casino proposal that Abramoff's clients opposed.