New polls released on Wednesday and Thursday continue to show President Barack Obama holding narrow leads in a handful of critical battleground states, but running within a whisker of Republican presidential nominee Mitt Romney nationwide.

While Romney gained significantly in the wake of the first presidential debate in early October, the lack of a continuing trend over the past two weeks helps counter a theme in some campaign coverage that Romney's support continues to "surge" nationwide.

The most recent updates of the seven daily national tracking polls continue to split in terms of which candidate holds the nominal lead...

...Collectively, the trends of the past week provide a reality check to two myths that have emerged in recent campaign coverage.

The first is that Romney has been "surging" since the first debate. While the debate certainly boosted Romney's standing in the polls, trends over the past two weeks have been negligible, with the leader seesawing nationally within a range of roughly one percentage point. Over the same period, the standings within the key battleground states have also remained constant. Other poll tracking models have shown the same patterns.

The second myth is that the national and battleground states polls have produced widely divergent results. If we use the state estimates produced by the Pollster tracking model in the nine key battlegrounds (Iowa, Wisconsin, Nevada, Ohio, New Hampshire, Colorado, Virginia, Florida and North Carolina) to create a combined total vote based on the turnout in each state in 2008, we show Obama leading in across all nine states by a slim 0.6 percentage point margin (47.8 to 47.2 percent as of this writing; the estimated margin would be 47.9 to 47.2 percent if based on the 2004 turnout).

Romney does slightly better in the national popular vote estimate, of course, but his 0.2 percentage point advantage there is only slightly better. The net gap is less than a percentage point.

As the Cook Political Report's David Wasserman writes on Twitter, simply subtracting 4 percentage points from Obama's 2008 margins in each state produces a similar result: "He'd lose Popular vote by 0.7% but still win w/ 272 EC votes."