What to watch in the Aug. 4 primaries: Michigan Senate race tests Democrats' path forward

Michigan will offer the country its clearest gauge yet on the direction of the Democratic Party, as primary voters in the battleground state choose between a progressive standard-bearer and an establishment-backed candidate.

Although there have been similar contests around the country, this one will hold extra weight because Michigan is a key state in presidential races. Abdul El-Sayed, backed by Sen. Bernie Sanders, is up against four-term Rep. Haley Stevens, supported by Senate Democratic leader Chuck Schumer.

Democratic and Republican voters in Michigan are also deciding on their parties' nominees to succeed term-limited Democratic Gov. Gretchen Whitmer.

In Kansas, Missouri, Virginia and Washington state, voters are settling primaries in a host of races, including a key rematch between Democrats in a Missouri House contest. Also in play is whether Democrats, who tried to redraw districts in Virginia to their advantage but were rebuffed by the state supreme court, can pick candidates who can defeat Republicans in the fall.

The choice between El-Sayed and Stevens has become a focal point for Democrats this year, and the race has become bitter. Whoever wins will need to bring splintered factions back into the fold to beat Republican Mike Rogers, a former congressman.

The seat is open because Democratic Sen. Gary Peters is retiring, and Democrats are under pressure to defend it to preserve their chance of winning control of the chamber.

Another dynamic at play has been the influence of the American Israel Public Affairs Committee, or AIPAC and its affiliated groups, which have spent nearly $30 million supporting Stevens.

The issue has become a lightning rod in Democratic politics since the Gaza war has split the party over U.S. backing of Israel. AIPAC backs candidates who support strengthening U.S.-Israeli relations. It's a significant issue in Michigan, which is home to the country's largest Arab American population.

El-Sayed cast the spending as a question of whether grassroots organizing can overcome millions in outside contributions.

That tension was also at play in 2024 when Democratic activists pressured now-Michigan Sen. Elissa Slotkin to take a harder line on Israel's war in Gaza. Slotkin, who is Jewish, had already distanced herself from AIPAC earlier. She ultimately defeated Rogers by fewer than 20,000 votes.

Rogers is running for Senate again this year, and is unopposed in the GOP primary.

Republican voters will decide on their nominee for Michigan governor on Tuesday as well. President Donald Trump has endorsed Rep. John James.

The president's backing typically carries significant weight in Republican politics, but there could be a complicating factor. Businessman Perry Johnson has loaned his campaign more than $30 million, according to Michigan campaign finance records.

A similar dynamic played out this year in Georgia's race for governor, where Rick Jackson spent $100 million, largely of his own money, to overcome the Trump-backed Burt Jones in a runoff.

On the Democratic side, Secretary of State Jocelyn Benson faces Genesee County Sheriff Chris Swanson.