With primaries today in Oregon and Kentucky, it's time again to play "Which Poll Do You Believe?" in the Democratic race for the White House.

We have certainly had more than enough examples this year of polling that has missed the mark by a little and by a lot, both before election day and in exit polls as well.

This time we have Oregon and Kentucky to look at, with Barack Obama seemingly the logical favorite in Oregon and Hillary Clinton the leader in Kentucky.

First, let's stop in the Bluegrass State, where political demographics again suggest that Clinton should win by a very comfortable margin tonight.

I'm not sure it will be a 41 point blowout like we saw a week ago in West Virginia, but we'll see.  The latest polls show a range of Clinton up 25 to 36 points.

To my gut, that seems about right.  Clinton has spent a good deal of time there over the last week, while Obama has sidestepped the fight, much as he did in West Virginia.

The day before the primary, Obama wasn't anywhere near Kentucky, as he campaigned instead in Montana, which votes two weeks from today.

Obama did spend a good chunk of time in Oregon, where he had that mammoth rally on Sunday afternoon.

The last two polls to come out there show a tight race, with Obama only up 4 points in one and five points in another.

Earlier polls had Obama up double digits, with one as high as 20 points.

I'm not sure I believe a twenty point bulge for Obama, but I could certainly see him ahead by double digits.

But what if these latest two polls are right and the edge is five points or less?  How can that be?

One group that has been polling in both states is American Research Group, which found a 36 point lead for Clinton in Kentucky and a five point lead for Obama in Oregon.

For the record, their final poll in West Virginia showed Clinton winning by 43 points (her actual margin was 41) and they had Clinton up by 8 points in Indiana - she won by two.

A review of polling so far by political analyst Stu Rothenberg found that ARG correctly called seven contests, but badly missed four others in which they did polling.

"Everyone seems to conduct polls these days, but not everyone conducts good ones," said Rothenberg on his website.

"That's the message I drew after reviewing dozens of presidential polls conducted from Iowa through Indiana and North Carolina."

Rothenberg said he found Survey USA the most credible, as he noted that they've done polling for him.

Survey USA has polled in both Oregon and Kentucky.  In Oregon, Obama was up 11 points in their poll and Clinton was up 34 points in Kentucky.

My gut tells me something around there is what I would bet on as well, but we'll see what the voters decide.