There is no better example of how critical primary elections are in deciding who gets elected than what is happening within the Democratic Party to oust incumbents that progressives view as establishment figures.
It is a strategy that voters have seen used in the Republican Party by mobilized grassroots movements like the Tea Party and MAGA to realign the party and its priorities.
Now, Democratic leaders have been put on notice that progressives are trying to build their own MAGA movement ahead of the 2026 midterm elections -- and the call is coming from inside the house.
DNC Vice Chair David Hogg, who survived the 2018 Parkland school shooting, announced a $20 million initiative last Monday to launch primary challenges against incumbents in safe seats.
The Democrats that will be targeted are not solely incumbents that have been in office for a long time, but anyone Hogg's group, Leaders We Deserve, deems as "incapable of meeting the moment."
“Earlier somebody said to me, ‘Oh, you’re here to replace the old with new.’ I would say we’re here to replace the ineffective with the new and effective,” Hogg said.
This has highlighted a rift with members of the Democratic Party who believe the party should focus on institutional centrism. However, elected officials critical of Hogg are reluctant to go on the record and be named.
For example, Axios spoke to multiple Democrats who were quoted on the condition of anonymity. One Democrat said it "seems inappropriate for a DNC vice chair to threaten sitting Dems."
Most members of Congress, regardless of party, know that the most consequential election on their path to re-election is the primary. This is because about 90% of seats in the US House are safe for one party or the other.
Not only does this mean elected officials are most vulnerable in primary elections, but because these elections tend to draw low turnouts, it wouldn't take that many voters to unseat them.
The better elections group Unite America found that only 14% of eligible voters in 2024 cast a meaningful vote in US House races, a figure that could dramatically drop depending on the state.
This is why the threat of being primaried has been used to keep party members in line.
Congressional Democrats clearly understand how serious this threat is to their political careers considering they don't want to have their names attached to any criticism.
Public opinion polling could also point to an appetite for a broad change in party leadership. A CNN poll from March, for example, found that a majority of Democrats believe their party is headed in the wrong direction.
The party's favorability among members and aligned voters was also at 63% -- almost a 20-percentage point drop compared to when former President Joe Biden took office in January 2021.
That kind of difference is enough to reshape primary elections.
On Wednesday, Our Revolution, an independent political organizing group born out of US Sen. Bernie Sanders' 2016 presidential campaign, released results of its own poll.
The group said in an email to supporters that it surveyed more than 4,100 politically active progressives and Democratic aligned voters and found that 92% of respondents supported primarying establishment Democrats.
Further, 88% said the Democratic Senatorial Campaign Committee and the Democratic Congressional Campaign Committee should stop automatically protecting incumbents.
The poll was obviously conducted with an agenda in mind. However, the warning signs for incumbent Democrats continue to stack up and go beyond public opinion polls.
Along with Hogg's initiative, US Sen. Bernie Sanders and US Rep Alexandria Ocasio Cortez (both progressive leaders) wrapped up a series of rallies in the western US that combined drew over 100,000 voters.
The 2026 primary elections could see the biggest internal fight within the Democratic Party in modern history -- and not only could it lead to a shift in power in Congress, but a complete party realignment.
While this isn't new to the Republican Party, it is something that hasn't been seen in the Democratic Party in quite a while.