From the Freedom Caucus to the democratic socialists, small groups inside parties can wreak havoc with leaders’ agenda in Congress

The Democratic Party’s coalition headed into the 2026 midterms is as broad as it’s been in years. That seems likely to help them pick up dozens of seats in Congress and win majorities back from Republicans in either or both chambers.

One notable and attention-getting portion of that coalition is a group of progressive political newcomers who affiliate with the Democratic Socialists of America, or DSA. This growing left-wing organization had a hand in the 2025 election of New York City Mayor Zohran Mamdani and has high-profile allies in Congress, including U.S. Rep. Alexandria Ocasio-Cortez, a New York Democrat, and U.S. Sen. Bernie Sanders, the independent from Vermont.

In the 2026 election cycle, DSA-affiliated candidates have won a handful of Democratic primaries. Most did so in districts that Democrats are very likely to win in November. As a result, at least a half-dozen DSA-affiliated candidates are all but guaranteed a seat in the next Congress.

But history tells us that a “big tent” party is also likely to face big divisions and even bigger challenges when putting together a governing coalition in Congress. Depending on the size of the Democrats’ possible majorities, the DSA-affiliated lawmakers’ reach and power, despite their small numbers, could extend beyond elections and deep into the process of legislating.

The challenge of selecting a leader

Before any policy can even be debated, Congress has to elect its leadership. In the Senate, the party with the most seats selects the “majority leader” and the other party the “minority leader.” This vote is fully internal to each party: Democratic senators will vote on their leader and Republicans on theirs. But in the House, this vote is on full display. Per the Constitution, the full House must select the speaker of the House. Because only a simple majority is required to win, the majority party typically dominates the speaker selection process.

While these processes seem simple on paper, they may be a hurdle for relatively unpopular Democratic leaders facing an ideologically divided caucus and slim margins of control. This is particularly true in the House, where a public, on-the-record roll call vote may pressure some members to rebel against the Democrats’ current House minority leader, Hakeem Jeffries of New York, who is largely presumed to be the next Democratic speaker.

For evidence of this potential, look no further than the 118th Congress: Following the election of a new Republican majority in 2023, then-leader Kevin McCarthy, a California Republican, faced a grueling 15 rounds of ballots before finally being elected speaker. The culprit? The ideologically extreme, far-right members of the Republican Party that didn’t want to support him.

Who the speaker is, and to whom they are beholden in their caucus, matters greatly for the policy goals of the upcoming 120th Congress.

Costs of compromise

The speaker controls House floor proceedings, shepherding legislation to the floor or preventing it from ever seeing a vote. They also head the steering committee, which determines committee assignments, manages a large and powerful staff, and controls the messaging of constituent communication.

For a speaker faced with managing an ideologically diverse coalition, these procedural advantages can be tools to protect their party from tough votes or, perhaps, to appease ideological extremists.

But as leaders of both their party and the entire chamber, balancing the demands of partisan peers can come into conflict with the necessities of lawmaking.

For instance, despite making policy and procedural deals with conservative members in his leadership bid, Speaker McCarthy was ultimately removed from office by his own party less than 10 months later for the transgression of compromising with moderate Democratic members to prevent a government shutdown.

While compromise may be necessary for a functioning government, it’s also antithetical to the goals of the conservative movement.

The man who took over the GOP leader’s job, current Speaker Mike Johnson of Louisiana, appears to have learned from this lesson: In the 119th Congress, his leadership has been defined by his deference to President Donald Trump and party conservatives, rather than trying to find the moderate middle between the two parties.

As Democratic leaders look to the upcoming 120th Congress, this same policymaking challenge will likely await them as well, regardless of which Democrat wins control of the speaker’s gavel.

Advantages of size and discipline

Yet ideological alignment alone is not enough to accelerate chamber action. Key to the success of any group seeking power in Congress is the size of its party’s advantage over the minority and the ability of ideological groups to organize.

That’s because narrow margins between the two parties force the majority’s leaders to pay attention to the demands of every member of their caucus in any effort to pass legislation.

Large majorities, meanwhile, can allow errant members to wander, with little risk to the majority party’s policy goals. And in 2026, with the median prediction in some models giving Democrats control of the House by as many as 30 seats, the half-dozen or so DSA-affiliated members may not always be essential to passing legislation.

Yet margin size alone does not guarantee clout. Groups must also be organized and cohesive.

In order for any ideological group to have a say in policymaking, it must not only be unified in policy goals but prepared to act as a voting bloc in the face of leadership. A potential DSA insurgency could take heed of the lessons of the conservative – and effective – Freedom Caucus before it, just one recent example from a long history of ideological rebellions in Congress.

But when ideological groups are disorganized, they don’t have much power to influence policy. So the ample resources and processes available to party leaders present an opportunity for the leader-driven lawmaking that has defined much of the modern congressional era.

The realities of effective lawmaking

Even the most organized, ideologically driven coalitions face a few underlying realities of lawmaking that political science tells us remain true.

For one thing, despite its reported demise as a victim of polarization and more recent bare-knuckle partisanship, bipartisanship still produces many significant legislative agreements in Congress. The 21st Century Road to Housing Act to increase access to affordable housing, the CHIPS and Science Act to encourage domestic technological development, and the First Step Act to reduce rising prison populations are recent examples of major bipartisanship policy solutions. And research has shown that members who attract more bipartisan co-sponsors tend to be more successful legislators.

Furthermore, most of these likely-to-be-elected DSA members are either political newcomers or have been successful only outside of the traditional Democratic establishment. This may have been a selling point in their primary campaigns, but these new members’ lack of experience and lack of experienced staff could limit their ability to maneuver in a Congress that even today is heavily structured by rules and norms, many of which are dictated by party leadership.

Leadership also has key institutional advantages that even the most fiery new members of Congress may find themselves unable to overcome.

Evidence since the 1970s demonstrates the deteriorating lawmaking capacity of individual members, particularly compared to party leaders. That makes it difficult for any member of Congress – particularly new, inexperienced members – to direct floor activity or get consideration of their biggest policy priorities.

DSA-affiliated members may be able to enhance their power by forming coalitions with other younger, establishment-skeptical new members, or with more experienced progressives such as Democrats Ayanna Pressley of Massachusetts or Maxwell Frost from Florida. These members may share many of the DSA’s values but do not specifically affiliate with their political movement.

As leaders of both their chambers and their parties, speakers and majority leaders have a responsibility to pass necessary legislation. But in cases of tight margins and well-organized ideological caucuses, the job of negotiating often comes within their own membership.