A republican polling organization called McLaughlin and Associates has a poll listed on pollingreport.com that shows Obama leading McCain 46-38%. Having been conducted June 26-29, this is the biggest lead in any national poll has shown for Obama since the LA Times/Bloomberg poll, concluded June 23, showed Obama winning by 15%. This lead is larger than the one Obama has in the poll conducted by Democracy Corps, a democratic pollster, by 5 points.
I have not seen or heard any reference to this poll other than this listing. The results are not even reported on the organization's own website. As of yet this poll has not been figured into the pollster.com composite averages. (I don't go to RCP on principal--if someone else wants to check to see if they are listing and figuring it into their composite feel free to post the info in the comments.)
I wouldn't attribute the lack of attention this poll is getting to a deliberate attempt at suppression--since the organization itself isn't pushing the data I can't blame media outlets for not running it. In fact, they often don't report partisan polls anyway, although pollster.com does include partisan polls in its averages.
Nevertheless, it's good to at least be mindful of this poll, especially considering its partisan origins.