The most important swing county in each state

[BaldEagle1991]

Massachusetts:  Barnstable (national bellweather, though a case could be made for Norfolk or Essex given Romney's home state advantage), Hampden (decides state)

Plymouth is more of a bellweather than any of these I think.

No, Plymouth has been heavily trending Republican (Obama won it by the same margin as nationally last time, compared to Kerry who did 11% better than nationwide, and Gore who did 15% better).

But yet it's still the most GOP county in MA. That has potential for a swing county, I think if Romney campaigns well and if the economy collapses again, that county will be a Romney County.

[crypto-fascist superhero]

Massachusetts:  Barnstable (national bellweather, though a case could be made for Norfolk or Essex given Romney's home state advantage), Hampden (decides state)

Plymouth is more of a bellweather than any of these I think.

No, Plymouth has been heavily trending Republican (Obama won it by the same margin as nationally last time, compared to Kerry who did 11% better than nationwide, and Gore who did 15% better).

But yet it's still the most GOP county in MA. That has potential for a swing county, I think if Romney campaigns well and if the economy collapses again, that county will be a Romney County.

That's my point...  Plymouth is almost certainly going to be more Republican than the country this year, and so is not a bellweather county.

[WhyteRain]

Just guessing, but I would say in Texas those counties would be Bexar (major city:  San Antonio) or Nueces (Corpus Christi).   But maybe as a South Texan I'm biased.

[HockeyDude]

My home county of Burlington always seems to mirror New Jersey's statewide results.  And why not?  It's got some Democratic blue collar areas near the Delaware (Riverside, Palmyra, Bordentown), some affluent somewhat rich Republican suburbs (Tabernacle, Shamong), some affluent somewhat middle class Democratic suburbs (Moorestown, Mt. Laurel), and is very diverse. 

[Minnesota Mike]

That's not how elections work.

[BaldEagle1991]

Just guessing, but I would say in Texas those counties would be Bexar (major city:  San Antonio) or Nueces (Corpus Christi).   But maybe as a South Texan I'm biased.

They're swing f course, but unlike Harris County (Houston), they have a strong military presence, that might work against it. 

[○∙◄☻¥tπ[╪AV┼cVê└]

I calculated this for states that held Senate elections in 2010 by using state PVIs here.

Those were just the counties closest to the statewide average for one election. Alpine, Calfiornia certainly fails as a bellwether long term.

I used PVIs, so it's the counties closest to the statewide average over the past two Presidential elections, not just 2008.  By definition, that shows recent trends, not long-term trends.  Alpine, California was a decent bellwether for recent Presidential elections - as good as Santa Barbara and Imperial and slightly better than San Benito, which was pretty decent, too.

Well, San Benito was a better bellwether than Alpine for this Prop. 29 that we still don't know whether it passed. Strangely, Los Angeles was even better.

[BaldEagle1991]

What about Jefferson County, Alabama?

[cope1989]

Well, most of the counties that swing back and forth are tiny backwoods counties in South Georgia that are 50/50 black and white, so they're not exactly representative of the country or national trends.

Someone mentioned Gwinnett earlier. I think that's a good choice. Previously it had been deep red, but it's diversifying and trending to the Democrats quickly. But it still has a very large conservative white base. In the next few cycles I can see it going back and forth.

Cobb county could become a swing county in the future. And as two of the largest counties in the state, they would certainly become the most important swing counties as well.

[Gass3268]

Micah Cohen over at 538 is running a series on Presidential Geography and part of his state by state write up is indicating the bellwether county in each state. I'll post here the list so far and I'll update it when he posts new posts.

Georgia: Lowndes County (Valdosta)
Montana: Yellowstone County (Billings)
New Hampshire: Merrimack County (Concord)
New Mexico: Sandoval County (Rio Rancho/Albuquerque Suburb)  

[GPORTER]

Micah Cohen over at 538 is running a series on Presidential Geography and part of his state by state write up is indicating the bellwether county in each state. I'll post here the list so far and I'll update it when he posts new posts.

Montana: Yellowstone County (Billings)
New Mexico: Sandoval County (Rio Rancho/Albuquerque Suburb) 

Yellowstone county is key in the Montana senate race. The republican name, his name escapes me at the moment though it shouldn't, but the former republican senator from that state who lost in 2006. He narrowly won yellowstone county in '06, but lost anyway.

[Gass3268]

Micah Cohen over at 538 is running a series on Presidential Geography and part of his state by state write up is indicating the bellwether county in each state. I'll post here the list so far and I'll update it when he posts new posts.

Montana: Yellowstone County (Billings)
New Mexico: Sandoval County (Rio Rancho/Albuquerque Suburb) 

Yellowstone county is key in the Montana senate race. The republican name, his name escapes me at the moment though it shouldn't, but the former republican senator from that state who lost in 2006. He narrowly won yellowstone county in '06, but lost anyway.

Cohen was saying that the main thing for Democrats in the state is to get big margins in the western part of the state and keep the margins low in Yellowstone County.

[Gass3268]

Added New Hampshire

[timothyinMD]

Jefferson Co, Colorado is the epitome

2008:
Statewide   53.66 O 44.71 M  [+8.95 O]
Jefferson Co 53.60 O 44.61 M [+8.99 O]

[Gass3268]

Added Georgia

[BaldEagle1991]

I was thinking Gwinett County, GA was the swing county in GA?