Should Democrats manage to retake the House during this year’s midterm elections, Minority Leader Hakeem Jeffries would likely become Speaker, replacing Louisiana Republican Mike Johnson.

But were that to happen, Jeffries’ leadership would likely be tested—daily—by the rising faction of left-wing socialists taking over the party.

A series of victories by progressive candidates in Democratic primaries has energized the party’s left wing and will create new challenges for the New York Democrat, The Hill noted on Thursday.

The results come amid growing calls from Democratic voters for a new direction within the party.

That sentiment was evident in Michigan last week, where progressive candidate Donavan McKinney, who was backed by far-left socialist Sen. Bernie Sanders (Vt.), defeated Rep. Shri Thanedar (D-Mich.) in the Democratic primary.

In another closely watched race, progressive candidate Abdul El-Sayed defeated Rep. Haley Stevens (D-Mich.), a longtime moderate, in Michigan’s Democratic Senate primary.

The outcome was viewed as another significant victory for the party’s progressive movement and added momentum to its recent electoral successes.