One of the Democrats' major challenges at their convention in Denver this week would appear to be the need to solidify the Democratic Party base. Gallup analysis shows that John McCain is now getting about 10 points more support from his Republican base than is Obama from his Democratic base.
Democratic presidential nominee-to-be Barack Obama has slipped slightly in his standing against McCain in recent days. Gallup does about 7,000 interviews a week as part of its ongoing tracking program, including interviews with over 6,000 registered voters. These very large sample sizes give us the ability to document even relatively small changes in the standings of candidates in the race.
Gallup's interviews with 6,205 registered voters during the week of August 18-24 show a dead-even race, 45% for Obama and 45% for McCain. The previous week, Obama led by a two percentage point margin, and before that held a 5-point margin. Overall, Obama led by three points on average in June and July. So we are seeing a slight, but real, tightening of the race. This past week is, in fact, the first week of the summer in which Obama has not led by at least one point.
Our analysis of the data suggests that McCain has, to a modest degree, increased his support among his base. During this past week, McCain received 87% of the vote of Republicans. That's the highest of the entire summer. Overall this summer, McCain has averaged 84% of the support of Republicans.
Obama's support among Democrats has been lower than McCain's among Republicans all summer. This past week, Obama received 78% support from Democrats. Not only is that nine points lower than McCain's support among Republicans, but it's the lowest partisan support for Obama of the summer, by one point.
So McCain has edged up a few points among his own base while Obama has edged down. (Obama's current 1-point lead among independents is about what we have seen for much of the summer.)
Obama has been helped by the fact that more Americans identify as Democrats than as Republicans. That's still the case. Last week's aggregate of registered voters showed 36% Democratic identifiers, 29% Republican, and 35% independent. That 29% Republican is up slightly compared to previous weeks, but we'll have to wait to see if that represents a trend.
Certainly these data show there is room for Democrats to shore up their base. If Obama simply were to match McCain in terms of loyalty of his own partisans in support of his candidacy, he would have a sizable lead over the Republican nominee.
One source of that conversion could be Hillary Clinton-supporting Democrats. The weekend USA Today/Gallup Poll showed that Democrats who were previous Hillary Clinton supporters were much less likely to say they were "certain" Obama voters than were previous Obama voters. More importantly, 16% of Hillary Clinton Democrats said they were supporting McCain, and another 14% said they were unsure or undecided. This may be a natural process for disgruntled party members whose candidate did not win the nomination, yet it represents a very real block of Democrats who, right now, are not giving their support to Obama.
