Majority of Obama's support comes from Democrats, according to my math

[antiimperialist]

One fellow DU'er posted a thread in which he linked to a Talkleft diary claiming that "Majority of Obama Support Not From Democrats".
But my calculations lead me to conclude that this is not the case.

Here it goes:

DMR polled 800 likely voters, broken down as follows:

400 Democrats (55% of all respondents)
320 Independents (40% of all respondents)
40 Republicans (5% of all respondents )

Obama gets 27% of the Democratic vote= 130 Dems
Obama gets 39% of the Independent vote=100 Ind.
Total of Obama's support=230 votes, plus the number of 40 Republicans who chose Obama. Unfortunately, the poll gave us no breakdown of Republican support for each candidate.

As you can see, Obama has the vote of 30 more Democrats than independents, before calculating support among the small 5% of Republicans. Even if 100% of the Republicans had chosen Obama as their favorite in this poll, this would be a tie (130% Democrats for Obama vs. 130 non-Democrats for Obama).

Assuming the very likely scenario that not all Republicans chose Obama, we are left with the conclusion that most of Obama's supporters are Democrats, though by a modest margin.

[IndianaJones]

1. I wouldn't call that a huge leap. nt.

[maximusveritas]

2. It's a meaningless point anyway

What's wrong with Independents?
I'm one. And I've always voted for Democrats in General Elections.

[dsc]

3. 100% of 40 is 40

so if he had 100% among GOP then he wouldn't be tied. He would have 140 indy/GOP and 130 Dem. The break even point is a split of 35 to 5 or 87.5%. Incidently to find out his exact number just take his percent in this poll, multiply by 800, and subtract the 230 people you have already accounted for. The number you get will be the number who vote for him and are GOP.

editted to fix typo.

[antiimperialist]

4. I'm confused, but you are right on the 100% of 40 being 40

For some reason I wrote 30.
So what is the percentage of Republicans who chose Obama, again?

[antiimperialist]

5. And note that Talkleft said it takes 40% pro-Obama Republicans for this to be true

But even if Obama gets 85% of Republicans, which is 34 Republicans out of 40, he would still get the support mostly from Democrats

100+34=134 non-Democrats
130+6=136 Democrats

[dsc]

6. Here goes

Take his total percent in the poll, say 35%.

35% of 800 is 280. Thus 280 people, in total, voted for him. You have accounted for 230. That leaves 50, so we know his support wasn't really 35%. BTW you are confused because I had a typo. It should have been 800, not 400.

On edit You have accounted for 230 and he would need 35 more for there to be an even number of dem and non dem supporters. That is 265 total which is just barely over 33%. So if he has 33% or more in the poll then he probably has a majority of his support coming from non dems. If he is less than 33% then the majority of his support is dem.

[OHdem10]

7. One people involved in the poll stated clearly most of Obama's

support comes from GOP and Independents. She was decisive in her
answer.

[antiimperialist]

8. Thanks. Do you have a link? nt

[papau]

10. see post below - the math is clear - most Obama votes are from Non-Dem's

[antiimperialist]

12. I think you didn't understand. I asked you for a link

You say that the "one people involved in the poll" said his support comes mostly from non-Democrats.
Can you give me a link? Nothing is said in the Demoines Register poll story about Obama getting most of his support from non-Democrats.

[papau]

13. the "link" is the actual article and then applying the numbers in the article

http://www.desmoinesregister.com/apps/pbcs.dll/article?AID=/20080101/NEWS09/301010015/-1/iowapoll07

"Clinton remains the favorite of the party faithful, with support from a third of self-described Democrats. However, Obama is the clear choice of caucusgoers who affiliate with neither the Democrat or Republican parties, with roughly 40 percent of them backing him in the survey.

The support from non-Democrats is significant because a whopping 40 percent of those planning to attend described themselves as independent and another 5 percent as Republican. Only registered Democrats can participate in the caucuses, although rules allow participants to change their party registration on their way in to the caucuses."

(BUT NOTE THE REGISTER JUST CHANGED THEIR TURNOUT MODEL TO INCLUDE FEWER DEMOCRATS AND MORE INDEPENDENTS - USING 2004 MODEL CLINTON ACTUALLY LEADS)

From latest poll:

[papau]

9. Poll had 727 people with 232 for Obama split 108 Dem and 124 non-Dem

reported 32% is 232 votes for Obama

55% of 727 is 400 Democrats.

27% of 400 is 108 Dem votes for Obama

108 plus 124 equal total votes for Obama =232

[antiimperialist]

11. Pollster.com and the Desmoine Register website say 800 likely Democratic caucus goers, not 727

http://www.pollster.com/blogs/poll_des_moines_registerselzer_1.php
http://www.desmoinesregister.com/apps/pbcs.dll/article?AID=/20071231/NEWS09/71231044/-1/iowapoll07

[papau]

14. The 400 and 55% mean 727 - if 55% and 800 total the excess non-Dem for Obama is larger