The effort to enact climate and energy legislation this year suffered a critical blow Saturday when Sen. Lindsey O. Graham (S.C.), the key Republican proponent of the bill, said he was unwilling to move ahead because of Democrats' push for immigration reform. The move forced the other two authors of the bill, Sens. John F. Kerry (D-Mass.) and Joseph I. Lieberman (I-Conn.), to cancel a news conference planned for Monday that would have unveiled the climate and energy plan they negotiated with Graham, the only Republican who had been participating in the discussions. In an interview Saturday, Graham said he...