President Joe Biden is besting former President Donald Trump among union-household voters, according to merged data from the most recent national NBC News polls.

But Biden’s support from the key demographic group is down slightly from where it was in the 2020 presidential election.

Biden and Trump have battled for union support, especially in battleground Michigan, with Biden joining a union picket line in September and Trump holding his own competing event speaking at a nonunion auto parts company in the state.

Michigan holds its presidential primary Tuesday, with both candidates on the ballot in the separate Democratic and Republican primaries.

Overall, the combined results from the poll’s November and January surveys find 50% of voters from union households backing Biden in a hypothetical 2024 general election matchup, compared with 41% who support Trump.

That compares to Trump’s 4-point lead over Biden among all registered voters in the combined November/January polls, 47% to 43%.

Yet Biden’s narrow 9-point lead among union-household voters in the NBC News polling is down from his 16-point advantage over Trump among that demographic in 2020, when the NBC News exit poll found Biden with a 56%-40% advantage among voters from union households.

The combined NBC News polling also finds Biden’s approval rating among union-household voters (46% approve, 52% disapprove) is higher than his overall approval rating (38% approve, 59% disapprove).

And union voters view Biden in a more favorable light (45% positive, 47% negative) than they view Trump (33% positive, 57% negative).

The poll numbers come from interviews with a combined 2,000 registered voters in the November 2023 and January NBC News polls, with a margin of error of plus or minus 2.2 percentage points. Of those total voters, a combined 412 say they or someone in their household is a current or retired union member, with a margin of error of plus or minus 4.8 percentage points among that group.

This article was originally published on NBCNews.com