LIVE UPDATES: Watch the full results of the special election in Wisconsin's 7th congressional district

• Voters in Wisconsin's 7th congressional district are voting in a special election to replace former Rep. Sean Duffy.
• State Senator Tom Tiffany is expected to defeat Democratic candidate Judge Tricia Zunker in this solidly Republican district.
• Polls close at 8 p.m. local time and 9 p.m. Eastern Time.
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Who are the candidates?

Republican State Senator Tom Tiffany is running against Democratic candidate Tricia Zunker in Wisconsin's 7th district, a largely rural area that encompasses much of northern and central Wisconsin.

Tiffany, a businessman and former local elected official, is serving his second term in the Wisconsin State Senate, while Zunker, an attorney, is a judge for the Ho-Chunk Nation and a member of the Wausau School Board.

Former Rep. Sean Duffy, who represented the district from 2011 to 2019, resigned before the end of his term last year for family reasons.

Tiffany is widely expected to defeat Zunker in this solidly Republican district. While former President Barack Obama won the district in both his 2008 and 2012 presidential runs, it's rapidly swung to the GOP since then.

President Donald Trump carried Wisconsin's 7th by 21 percentage points in 2016, and Duffy won his last election in 2018 by a 22-point margin over his Democratic opponent.

The special election also comes a month after Wisconsin's chaotic April 7 presidential primary and Supreme Court election.

After a prolonged and bitter standoff between Democratic Gov. Tony Evers and Republicans in the state legislature, thousands of voters did not receive or were unable to return their absentee ballots in time.

A shortage of poll workers in big cities like Milwaukee and Waukesha left voters standing in hours-long lines while waiting to vote. Milwaukee, which usually runs 180 polling places, operated with just five on election day.

While Wisconsin allows voters to request an absentee ballot without an excuse, the Wisconsin National Guard will also help staff polling places for the May 12 special election in the 7th district.