ABC News' Amy Walter reports: At a meeting with reporters yesterday afternoon a senior Democrat walked through the “untold story” of the 2010 election. While conceding that Republicans will gain seats in November, this Democrat contends that there are four significant, but underreported factors that will help Democrats hold the majority. 1) No Shut-Out: Democrats have 23 seats where they are playing offense. Of that list, they expect to win at least five seats. That would mean that Republicans would need to win at least 44 seats, not the 39 that currently separates Republicans from the majority. 2) Tea Party Problems: Democrats also point to a number of places where the Tea Party candidate upset the more electable GOP contender. While not as high-profile as their Senate counterparts (and none, as far as we know, has talked about witches or masturbation), these candidates, says this Democrat, are out of the mainstream. 3) Field Of Dreams: Then there’s the field game. For weeks now, Democrats have argued that despite being vastly outspent by outside groups on the airwaves, the GOP has not invested in the ground game like Democrats have. For example, AFL-CIO President Richard Trumka told reporters yesterday that organized labor is making its presence known on the ground and tailored specifically to their members. 4) Split The Difference: Finally, there’s the 3rd party factor. There will be “lots of incumbents who’ll be re-elected with less than 50 percent,” said this Democrat who pointed to nine races where a third party candidate could siphon off enough votes to help a vulnerable Democrat squeak to victory. So, will this work? In recent days both Democrats and Republicans have sought to tamp down talk that the GOP has “locked down” enough seats to gain control of the House. The most recent ABC/Washington Post poll showed a tightening in the generic ballot question – though Republicans still hold a significant 6 point lead. And, in 2006, the last time party control switched in the House, we saw plenty of races that were won/lost on the margins like this. But, in a wave year, as this is shaping up to be, the vast majority of seats end up breaking one way. In 2006, for example, the Cook Political Report listed 54 Republican seats as vulnerable. Demcrats ended up winning 30 of those – or 56 percent. This year, Cook has 81 Democratic seats listed as vulnerable. If we give Democrats the 5 GOP-held seats they say they’ll win, it would mean that Republicans would need to win, well, exactly the same percentage- 56 percent – that Democrats did just four years ago.