If Brown stays in Downing Street, it will be more a result of his rivals’ failed tactics than his own popularity. Local government elections on May 1 saw Labour’s share of the national vote drop to 24 percent, its lowest level in more than 40 years. Worse, a recent survey found 55 percent of party supporters said Labour would fare better with a new leader. But don’t expect a challenge just yet. Possible successors have stuck to praising the P.M. in public. Pundits say a leadership fight would only intensify the party’s image problems. An unpopular Brown may still be better than an unpopular party.