04 Polling Note, 7/23 – Convention Bounce

Bush and Kerry remain in a dead heat in a scrum of national polls today. Those, plus all state polls, are posted on the Polling Unit site on the intranet. (Click the "04 Election Spreadsheet.")

Separately, the following memo dissects the storied "convention bounce."

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What goes up does not always come down.

That's the charm of the "convention bounce," the jump in support that customarily accompanies a presidential candidate's nominating convention. Sometimes it's a short- term thing, the race quickly returning to form. But it can be a more profound event - a coalescing of public preferences that charts the course for the remaining campaign.

So it was in 1992, the Year of the Bounce. went into the Democratic convention one point behind George H.W. Bush - and left it 29 points ahead. Skeptics scoffed, calling it momentary. But it lasted: on to Election Day, Clinton never trailed.

The next-biggest bounce of recent times (since 1968) was ’s in 2000, a 19-point convention gain (compared to Clinton’s net of 30). But in Gore’s case it wasn’t enough.

Now it’s ’s turn, with George W. Bush to follow. Will they fly? If so, how high, and for how long?

FACTORS – The polls ahead will tell. But two factors this year may make it tougher than usual for the candidates to achieve a large or lasting bounce: attention to the race, and attachment to the candidates. Conventions can boost both these. But in these highly polarized days, attention already is high, and the candidates’ support already is strong and enthusiastic.

Heading into his 1992 convention, for example, just 46 percent of Clinton supporters were “strongly” behind him. As early as this April, by contrast, Kerry’s support was 65 percent strong – and Bush’s, 84 percent. In our most recent political poll, 72 percent of Kerry’s supporters said they’d “definitely” vote for him – compared with 58 percent for Gore in July 2000. Seventy-eight percent of Bush’s support is “definite,” up from 63 percent in July 2000. Eighty-three percent of Kerry’s supporters, and 90 percent of Bush’s, describe themselves as “enthusiastic” about their guy. And eight in 10 registered voters are closely following the race, compared with 55 percent at this time in 2000 (admittedly a low-focus year).

Now Then Kerry Bush Gore Bush “Definite” support 72% 78 58% 63

That said, the ranks of currently undecided and less-than-definite supporters provide plenty of room for a Kerry bounce to occur, and a Bush bounce to follow. Which returns us to how high they go, and how long it lasts.

OH-OH – In 2000, when the Republicans went first, Bush stretched an insignificant three-point lead before his convention into an 11-point lead after it. That opened to a 14- point lead before the Democratic convention, from which Gore emerged with a five-point edge. Not enough: Their race soon devolved into the dead heat for the ages.

Other bounces have faded farther and faster. Bush’s father trailed by 21 points on the eve of his 1992 convention, then moved to within five after it. But it didn't hold: A week later he was back to a 19-point deficit.

While no convention bounce has matched Clinton's in 1992, many others are impressive in their own right. In 1976 's bounce to a 33-point lead underscored Gerald Ford's weakness. In 1980 Carter bounced from a 16-point deficit to a one-point lead. (It didn't last.) In 1984 Walter Mondale bounced from a 14-point deficit to a two-point lead. (It didn’t last.) And 1988’s bounces were gnarly: Mike Dukakis led by 17 points after his convention. G.H.W. Bush whittled that down to seven points before the Republican convention, bounced to a four-point post-convention lead, and went on to win.

The 1996 bounces produced less drama because the lead never changed hands. There was movement: advanced from a 19-point deficit before his primary to a four-point deficit after it. But that faded to a nine-point Dole deficit within a week, growing to 14 points after the Democratic convention.

Two candidates have been essentially bounceless: Hubert Humphrey trailed by 16 points before the ’68 Chicago convention and by 12 points after it. And in 1972 George McGovern went into his convention down by 16 points – and left it down by 19.

Customarily the bounce is given as the number of points gained by the candidate during his convention. But what happens to the other candidate - and the net change - are significant, too. We give them all here:

Net Change 2000 Rep. bounce Bush +6 Gore -5 Bush +11 Dem. bounce Gore +10 Bush -9 Gore +19

1996 Rep. bounce Dole +8 Clinton -7 Dole +15 Dem bounce Clinton +4 Dole -1 Clinton +5

1992 Dem. bounce Clinton +14 Bush -16 Clinton +30 Rep. bounce Bush +6 Clinton -10 Bush +16

1988 Dem. bounce Dukakis +7 Bush -4 Dukakis +11 Rep. bounce Bush +6 Dukakis -5 Bush +11

1984 Dem. bounce Mondale +9 Reagan -7 Mondale +16 Rep. bounce Reagan +4 Mondale -4 Reagan +8

1980 Rep. bounce Reagan +8 Carter -5 Reagan +13 Dem. bounce Carter +10 Reagan -7 Carter +17

1976 Dem. bounce Carter +9 Ford -7 Carter +16 Rep. bounce Ford +4 Carter -3 Ford +7

1972 Dem. bounce McGovern 0 Nixon +3 McGovern -3 Rep. bounce Nixon +7 McGovern -1 Nixon +8

1968 Rep. bounce Nixon +5 Humphrey -9 Nixon +14 Dem. bounce Humphrey +2 Nixon -2 Humphrey +4

For consistency these results are all among registered voters. 1992-2000 polls are from ABC News; 1968-88 polls by Gallup. Earlier polls weren't done frequently enough to track the convention bounce reliably.

NINETY-TWO – Again, for old-fashioned thrills, nothing has approached the Clinton and Bush bounces of 1992. Clinton went into his convention with 44 percent support and left it with 58 percent on July 19. (That's in a two-man race; Perot wasn't running at the time.) In the same period, Bush's support dived from 45 percent to 29 percent.

A month later, Clinton was still aloft, defying those who'd suggested his bounce had no legs: On Aug. 19, the eve of the Republican convention, he led by 57-32 percent. Bush's convention tightened the race to 47-42 percent, as close as it would be until the final days of the campaign. But, unlike Clinton's, Bush's convention bounce was very short-lived. By Aug. 30 the race was back to a 55-36 percent Clinton advantage.

The Polling Unit’s intranet site includes an Excel spreadsheet listing convention bounces since 1968 in greater detail, as well as all presidential horse race polls since 1936, and every state and national poll conducted to date in the '04 contest . Check the "election spreadsheets" section, or call for assistance.