McCain Surges as Obama's Biden Pick Flops in Public Opinion

The trends in polling this week are even more advantageous to the GOP than I've predicted thus far.

I argued previously that "Obama Will Get No Post-Denver Polling Bounce," but even with that I'm caught off guard by Gallup's latest tracking numbers finding John McCain leading Barack Obama 46 to 44 percent:

It's official: Barack Obama has received no bounce in voter support out of his selection of Sen. Joe Biden to be his vice presidential running mate.

Gallup Poll Daily tracking from Aug. 23-25, the first three-day period falling entirely after Obama's Saturday morning vice presidential announcement, shows 46% of national registered voters backing John McCain and 44% supporting Obama, not appreciably different from the previous week's standing for both candidates. This is the first time since Obama clinched the nomination in early June, though, that McCain has held any kind of advantage over Obama in Gallup Poll Daily tracking.

The race for president has been virtually tied since mid-August. In this period, Obama's support from national registered voters has consistently ranged from 44% to 46%. The 46% currently supporting McCain is technically his best showing since late May/early June, but is not a statistically significant improvement over his recent range from 43% to 45%. (To view the complete trend since March 7, 2008, click here.)

An analysis of historical election poll trends by Gallup Poll Managing Editor Jeff Jones shows that recent presidential campaigns have enjoyed a small (though short-lived) bounce from the running mate announcement. This includes a four percentage point bounce for John Kerry in 2004 after selecting John Edwards, a 5-point bounce for Al Gore in 2000 with his announcement of Joe Lieberman, and a 3-point bounce for George W. Bush in 2000 upon choosing Dick Cheney. Bob Dole received an extraordinary 9-point bounce in 1996 after bringing Jack Kemp onto his ticket.

All of these bounces occurred before the respective party's convention began, and in most cases the candidates received an additional boost in the polls upon completion of the convention. Thus, any increase in Obama's support in the coming days would seem to be more the result of the star-studded and well publicized Democratic national convention than the apparently lackluster Biden selection.

Note that while, yes, McCain's lead remains within the margin-of-error range, holding statistical significance aside, over the last week McCain's picked up 6 percent on Obama on a straight point basis.

Trend-wise, this is even better than I'd hoped. My expectation earlier was for Obama to stagnate this week, getting a small single-digit bounce coming out his acceptance speech, a lead that would collapse upon the announcement of McCain's running mate.

Hillary better knock a Mile High home run tonight at the Pepsi Center. Obama's lagging behind historical benchmarks, and the more I look at the data, the less favorable appear Democratic Party prospects, not only for a post-convention polling bounce, but for post-Labor Day campaign success as well.

Note finally, if McCain announces his vice-presidential running mate ahead of schedule, possibly on Thursday, the GOP may well chip into Obama's numbers even more (and a Thursday veep announcement could dramatically jumble the day's press cycle, surpressing the media bounce from Obama's acceptance speech in Denver).

Photo Credit: Cleveland Leader, "McCain Pulls Ahead of Obama in Second Poll this Month."