Abdul El-Sayed defeated Rep. Haley Stevens in Michigan's Democratic Senate primary race, winning approximately 49% of the vote, NBC reported on Wednesday.
Other news outlets have yet to call the results of the race, with the Associated Press reporting that 91% of the votes have been counted thus far.
El-Sayed has repeatedly spoken out against Israel, while Stevens is considered a pro-Israel candidate and was funded by AIPAC.
The contest has emerged as one of the clearest tests yet of the direction of the Democratic Party, pitting El-Sayed's campaign against Stevens, an establishment-backed moderate supported by Democratic leaders and pro-Israel groups.
Race showcases whether Democratic voters receptive to new candidate agendas
The race was being closely watched for clues about whether Democratic voters in a crucial swing state are receptive to candidates who challenge party leaders and champion an agenda focused on lowering costs, expanding healthcare coverage, and restricting the role of big money in elections.
Michigan is both a presidential battleground and home to one of the country's largest Arab American communities, making it an important testing ground for Democrats' electoral and ideological future.
The winner will face Republican Mike Rogers in November in a race critical to Democrats' hopes of regaining control of the US Senate.
This is a developing story.