The polls are open until 10.30pm tonight.
It's voting day in the first Dáil election in Ireland since the start of the pandemic.
Voters in Dublin Bay South will cast ballots to elect a replacement for former Fine Gael minister Eoghan Murphy.
Our Political Correspondent Seán Defoe reports:
"Ballot boxes open at the earlier-than-usual time of 7am this morning and will stay open until 10.30pm tonight, allowing more time for voting so people can space out when they arrive.
There are some changes to the typical election day due to Covid-19.
People in Dublin Bay South are asked not to vote if they're displaying Covid symptoms or are self-isolating.
Facemasks need to be worn in polling centres - and people are asked to bring their own pens or pencils to mark their ballots.
Photo ID will also be needed - and staff may ask people to briefly remove your mask to confirm identity.
There may be socially distant queues at busier times and people are asked to plan their voting for quieter periods.
All polling stations will be cleaned and sanitised every two and a half hours.
There's 15 candidates on the ballot for this by-election.
The votes will be moved to the RDS when ballot boxes close - with the count starting at 9am tomorrow morning."

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