"FOR a long time Dilma Rousseff looked invincible. Even huge nationwide protests last June, when millions of Brazilians took to the streets to air assorted grievances and disaffection with politicians, were not enough to depress the president's approval ratings below 45%. Her popularity quickly rebounded; Ms Rousseff seemed poised for a first-round win in a presidential election this October. A new poll, however, confirms what many observers have been saying for months: that Ms Rousseff's lead is more fragile than she and her Workers' Party (PT) would care to admit"