Democrats aren’t on the doorstep of re-taking the House majority in November, but they do stand a good chance of winning in about two dozen of the most blue-leaning seats held by Republicans, according to a new Democratic poll.

The Democracy Corps poll, by pollster Stan Greenberg and strategist James Carville, tested 54 targeted GOP-held districts. The poll shows Democrats aren’t as well-positioned as they were prior to the wave elections of 2006 or 2008 — or as Republicans were in 2010 — but there is a smaller sub-set of districts where Democrats are in a good spot to compete.

The poll shows Democrats lead on a hybrid generic ballot by an average of 50 percent to 44 percent in 27 GOP-held districts identified by the pollsters as “Tier 1” targets. Among the next 27 districts (“Tier 2”) Democrats trail by nine points, 50 percent to 41 percent.

If the numbers are accurate, though, that suggests Democrats could be in line for significant — if not majority-making — gains. The party needs to gain 25 seats in order to re-take the chamber, but the number is probably close to 30 when you factor in the handful of Democratic-held seats that Republicans are likely to win thanks to redistricting changes that turned the districts heavily in favor of the GOP.

Being ahead and at 50 percent is good position for any challenger — generic or not — and the fact that that’s the average of the polling in 27 districts means Democrats could be playing plenty of offense in the final 90 days of the election.

Two caveats are worth mentioning.

First, these polls test a generic Democrat against a named GOP incumbent or, where there is no GOP incumbent, a generic Democrat against a generic Republican. And generic candidates tend to perform better than unknown challengers, so these numbers likely paint a better picture for Democrats than regular head-to-head polling between Democratic challengers and GOP incumbents would.

Second, this is a partisan poll. And polls in which both candidates are named would probably paint a significantly better picture for the GOP. The National Republican Congressional Committee says its internal polling in these same 27 districts shows Republicans leading by an average of seven points in head-to-head matchups (in which both candidates are named) and by three points on the straight generic ballot (unnamed Republican vs. unnamed Democrat).

The truth, as it often is with internal polls, is probably somewhere in between the GOP polls and the Democratic polls. Which means these roughly two dozen seats should be competitive.

Cumulatively, when you factor in all 54 districts, though, the Democracy Corps poll shows a generic Democrat trailing by an average of 47 percent to 45 percent. That sounds close, but it doesn’t compare favorably to the last three elections, when the party that was primed for big gains led by an average of at least five points in targeted districts at this point. (Democrats won 54 seats combined in 2006 and 2008; the GOP won 63 seats in 2010.)

(Democracy Corps)

Translation: this year is not looking like a wave election.

But the poll suggests that even if the House majority isn’t yet in play — and most political observers agree that it’s pretty safe at this point — that doesn’t mean Democrats can’t roll back some of the significant GOP gains of 2010.

In many ways, the polling is as much a reflection of the makeup of these districts as anything else. Twenty five of the 27 “Tier 1” seats identified by Democracy Corps went for President Obama in the 2008 presidential election — about half of them by nine points or more — and Obama leads Mitt Romney the 2012 race in those districts by an average of 8 percent.

Republicans took a lot of blue-leaning territory in 2010 and now enjoy their biggest majority in 60 years, so it won’t be surprising if they lose some of those seats simply because the environment isn’t as friendly as it was two years ago.

The question from here until the election is how much incumbency is worth in these targeted districts and how well challengers perform.

As we’ve discussed before, the fact that many of the Republicans in these districts are freshmen who don’t have years of goodwill built up in their districts could make it harder for them to reap the advantages of incumbency and out-perform their presidential nominee.

But as long as Republicans can keep a fair chunk of those 27 top-targeted districts, they should be returning to Congress in 2013 with another majority. And right now, there’s little reason to believe they won’t be able to do that.