During the month of June, 37.0% of Americans identified themselves as Democrats, up from 36.4% in May. Only once in the past year have a larger share of American adults identified themselves as Democrats.

The number of Republicans remained essentially unchanged—33.5% in June and 33.6% in May.

However, the number of Americans unaffiliated with either major party dipped to 29.5% in June. That’s down half a point from 29.5% in May.

These results come from Rasmussen Reports tracking surveys of 15,000 voters per month. When the year began, our January reading found the Democrats with what is so far their lowest percentage of the year (36.1%) and the Republicans with their highest percentage (34.5%). The Democrats have trended up slightly to their current level of 37.0%, the highest percentage of 2006. For Republicans, the low point came in April (32.7%).

Democrats now have a net advantage of 3.3 percentage points over the GOP. In June of 2004, the Democrats had a 2.5 percentage point advantage. Please keep in mind that these figures are for all adults, not Likely Voters. Republicans typically do a bit better among Likely Voters (in fact, the two parties ended up even among those who showed up to vote in 2004).

Monthly data from January 2004 to May 2006 can be reviewed here.