Joe Biden (D) has a narrow lead in the crucial swing state of Wisconsin, a Trafalgar Group survey released Monday showed.

The survey, taken September 22 -24, among 1,189 respondents, showed the former vice president leading President Trump by 2.8 percent — 47.7 percent to Trump’s 44.9 percent. The survey’s margin of error is +/- 2.76 percent.

Jo Jorgensen, the libertarian candidate, garnered 2.5 percent support. Just over three percent remain undecided:

A federal judge ruled this month that absentee ballots can be counted six days after November 3 in Wisconsin, so long as they are postmarked by Election Day. However, the ruling also allows such ballots to be counted, even if there is no “definitive” sign of a postmark, as Breitbart News detailed:

U.S. District Judge William Conley of the Western District of Wisconsin — an appointee of President Barack Obama — ruled that absentee ballots in the state can be counted until Nov. 9 as long as they are postmarked by Election Day, Nov. 3. He cited the state’s difficult experience in the recent primary election, as well as projected difficulties with the U.S. Post Office as it handles an unprecedented number of mailed-in ballots.

In a footnote, Conley added:

Given the political deadlock among WEC Commissioners and the apparent lack of state law guidance on this subject — as well as the fact that this postmark requirement is federally mandated and the apparent importance of equal treatment of ballots after Bush v. Gore, 531 U.S. 98 (2000) — it is this court’s view that local election officials should generally err toward counting otherwise legitimate absentee ballots lacking a definitive postmark if received by mail after election day but no later than November 9, 2020, as long as the ballot is signed and witnessed on or before November 3, 2020, unless there is some reason to believe that the ballot was actually placed in the mail after election day.

President Trump defeated Hillary Clinton in the battleground state in 2016 by less than a single percentage point. Monday’s RealClearPolitics average showed Biden leading by 6.2 percent.