A resident arrives to vote in the state's primary election at a polling location on April 2 in Green Bay, Wisconsin.

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Most Americans have moved on from the presidential primaries now that they are effectively over. President Joe Biden and former President Donald Trump have amassed enough delegates to win the Democratic and Republican nomination, respectively.

But there was still an important message for Biden in particular from the results in Wisconsin’s primary on Tuesday, where progressives and pro-Palestinian Democrats did not support the Democratic president. As of early Wednesday morning, nearly 48,000 votes, or 8.3% of those cast, were for “uninstructed” in the Democratic primary.

Biden was actively shifting course Tuesday as he addresses increasingly loud concerns from the Muslim American community about the situation in Gaza.

He had been scheduled to attend a scaled-back iftar dinner commemorating Ramadan at the White House. But pushback from potential attendees led the White House to shift those plans and instead conduct a meeting with Muslim community leaders.

Trump, meanwhile, is holding general election rallies in Michigan and Wisconsin to focus on the issues of immigration and crime.

Wisconsin’s ‘uninstructed delegation’ vote

The primaries technically continue into June, and some progressive voters in particular are intent to use the process to send a message to Biden about his support for Israel during the deepening humanitarian crisis in Gaza.

That’s why there will be a fair amount of scrutiny of the fraction of people who don’t vote for Biden in the Democratic primary in Wisconsin but instead support an “uninstructed delegation.”

This is basically the same as voting for the “uncommitted” option that appears in many other states’ primary ballots.

Rather than sending delegates favoring Biden to the Democratic National Convention in Chicago in August or favoring Trump to the Republican National Convention in July in Milwaukee, these voters are instead voting to give delegates the power to pick whichever candidate the delegates want. It’s basically a message to the national parties and candidates that these voters are unhappy.

Heading into Tuesday’s contests, on the Democratic side, Biden had 2,606 delegates compared with 26 delegates spread across five states for “uncommitted” and three for Jason Palmer, the businessman who scored a surprise victory in the Democratic caucuses for American Samoa. On the Republican side, Trump had 1,686 delegates compared with 103 spread across three candidates, including former South Carolina Gov. Nikki Haley, who have since dropped out of the race.

There will be some number of voters who pick the “uninstructed” option in any year. Nearly 2% of Democratic primary voters opted for “uninstructed” instead of then-President Barack Obama in Wisconsin’s Democratic primary in 2012.

Michigan’s protest example

What’s different this year is that progressive and pro-Palestinian groups were actively encouraging voters in Wisconsin to pick the “uninstructed delegation.” A similar campaign in Michigan’s Democratic primary in February with the “uncommitted” option yielded more than 100,000 votes, about 13% of the primary vote count, compared with Biden’s 81%.

For comparison, 3% of Michigan Republican voters, more than 33,000, picked “uncommitted” over both Trump and Haley.

A volunteer holds a "Vote Uncommitted" sign outside of a polling station at Oakman School in Dearborn, Michigan, on Tuesday, February 27.

Any discontent could be consequential

Wisconsin, while it has a smaller Arab American voting population than Michigan, is one of those key battleground states that have been decided by slim margins in recent elections. Trump won the White House by winning states like Wisconsin in 2016 and then lost the White House when Biden took it back for Democrats in 2020.

Read this dispatch from CNN’s Jeff Zeleny and Gregory Krieg on the spoiler role Robert F. Kennedy Jr. could play as an independent candidate in a state like Wisconsin. They note that when the Green Party’s Jill Stein was a candidate in Wisconsin in 2016, Trump won. When Stein was off the ballot in 2020, he lost.

There was an “uncommitted” option on Tuesday’s presidential primary ballots in Connecticut and Rhode Island as well. New York also conducted a primary, but does not list “uncommitted” as an option.

RELATED: In quest to change voting rules, Republicans push ballot measures in key battleground states

A shift on Israel?

There have been some indications after the Michigan protest that Biden and other top Democrats were evolving on Israel.

The US recently allowed a Gaza ceasefire resolution to pass through the United Nations Security Council.

Senate Majority Leader Chuck Schumer, the top elected Jewish official in the country, called for a new election in Israel and sharply criticized Israeli Prime Minister Benjamin Netanyahu.

When a Biden event in North Carolina was interrupted by pro-Palestinian protesters, Biden admitted “they have a point.”

On the other hand, the Biden administration is on the cusp of approving a deal to sell up to 50 American-made F-15 fighter jets to Israel.

As returns roll in from the Wisconsin primary, Biden could have been attending the iftar dinner at the White House to commemorate Ramadan, but it was shifted to a meeting, clear evidence of the frustration he is getting from the Muslim community.

Navigating how to support Israel is complicated for both Biden and Trump. The New York Times recently reported that Trump alarmed right-wing journalists from Israel when he told them in an interview that Israel should “finish up” in Gaza. Whether it was advice or a demand, the comments were far from the full-throated support for Israel that US conservatives might expect.