<p>The hole the US Democratic party is digging for itself just keeps getting deeper. In the past few days, after the grisly reappearance of Jeremiah Wright – the former friend who came not to praise Barack Obama but to bury him – Hillary Clinton’s standing in the polls has improved again. In Tuesday’s primaries, she is hoping for a comfortable win in Indiana and a close result in North Carolina, a dramatic change from just a month ago.</p>