Former governor to run for Senate

Former Virginia Gov. Mark R. Warner will announce today that he is running for the U.S. Senate seat being vacated by Republican John W. Warner, setting the stage for one of the most competitive races in the country next year, according to sources familiar with his decision.

The former governor, 52, a self-described moderate Democrat, will make his announcement in an e-mail to supporters but won’t formally begin his campaign until after the state races in November. Democrats have been courting him in the hope his entry in next year’s race would help them retain their Senate majority.