Democrat Elwyn Tinklenberg leads U.S. Rep. Michele Bachmann (R.-Minn.) 47 percent to 44 percent in a new poll of 621 likely voters in Minnesota’s 6th Congressional District that Survey USA conducted Oct. 21–22 for KSTP-TV. The poll shows that 6 percent of respondents favored Independence Party candidate Bob Anderson and 2 percent were undecided. The poll has margin of error of plus or minus 4 percent.

Survey USA cautions that the poll is a snapshot from a volatile race that – with Tinklenberg’s lead within the margin of error — appears to be essentially tied. Indeed, the contest continues to develop as a national story on the news of Bachmann’s Oct. 19 remarks on MSNBC’s “Hardball” show. (On Friday MPR will release results from its own poll of 6th District voters’ current take on the race.) The day before Bachmann told MSNBC’s Chris Matthews that U.S. Sen. Barack Obama and possibly others in Congress held “anti-American” views, the Democratic Congressional Campaign Committee released results of a survey taken Oct. 10–12 showing Bachmann with a narrow 42–38 lead.

In the poll released Thursday, women preferred Tinklenberg to Bachmann by a wider margin (53 percent to 41 percent) than men favored Bachmann over Tinklenberg (48–42). Tinklenberg takes 51 percent of independent voters to Bachmann’s 35 percent. And the DFLer gets the support of more Democrats (87 percent) than Bachmann does Republicans (79 percent).

That last figure demonstrates that Republican support for Bachmann has dropped by 9 percentage points from where it stood two years ago, as reported in a poll that Survey USA took for KSTP-TV on Oct. 24–26, 2006, just days before Bachmann won election to her first term in Congress.

Major media are reporting that Survey USA conducted this week’s poll on Monday and Tuesday, but that’s incorrect. It turns out it was actually Tuesday and Wednesday, meaning that some respondents gave pollsters their voting preference when the controversy over Bachmann’s “anti-American” statements and re-statements had had yet another 24-hour news cycle in which to curdle.

The problem: Survey USA’s original report listed two different date ranges (Oct. 20–21 and Oct. 21–22) as the period over which the poll was conducted. Jay Leve, an official at the polling organization, issued this clarification early Friday in response to a Minnesota Independent query:

SurveyUSA apologizes for the confusion. Data collected 10/21/08 + 10/22/08. Poll released 10/23/08. The incorrect reference has been changed.