House Speaker Nancy Pelosi (D-Calif.) has been quite successful in holding her caucus together to win close votes on major pieces of legislation in recent weeks. The highest-profile bill the House has approved is President Biden’s $1.9 trillion American Rescue Plan Act, which passed March 10 by a vote of 220 to 211. Just one Democrat (Maine’s Jared Golden) joined Republicans in voting against the measure.

The House has also approved a number of other big bills by relatively narrow margins, including the Protecting the Right to Organize Act (225-206), the For the People Act (220-210),  and the George Floyd Justice in Policing Act (220-212).

On each of those votes, at least one Democrat broke with the caucus and voted with the Republicans. At the same time, on several measures, a handful of Republicans broke with their caucus to vote with the Democrats. (That was particularly true on the PRO Act, which drew five Republican votes.)

But there is not a lot of room to spare as Pelosi continues to push an ambitious agenda for hearings, debates, and votes.

And the Democratic majority is slowly dwindling—not because of election losses but because of President Biden’s appointments of House members to top jobs.

“They lost one member this past week after now-former Rep. Marcia Fudge (D-Ohio) was confirmed by the Senate on Wednesday to serve as Secretary of Housing and Urban Development. Their numbers will shrink even further once the Senate votes to confirm Rep. Deb Haaland (D-N.M.) as Interior secretary, something that is expected to take place Monday,” noted The Hill late last week. “That means Democrats will only be able to afford up to three defections and still pass legislation on their own while those vacancies remain unfilled.”

That means that five upcoming special elections will be watched closely, even if only a couple of them hold out remote chances that a seat might flip from one party to the other.

Here’s the schedule so far:

Louisiana District 2: March 20 initial vote, April 24 runoff

This contest to fill the New Orleans–based seat of former Representative Cedric Richmond, a Democrat who joined the Biden administration as a senior advisor to the president, is all but certain to produce a Democratic winner. Candidates of both parties, along with third-party and independent contenders, compete in the March 20 initial election. If no one gets 50 percent of the vote, the two top finishers compete on April 24.

The leading Democratic contenders are state senators Troy Carter and Karen Carter Peterson, along with community activist Gary Chambers Jr., who has attracted a good deal of progressive support.

Here’s some background on the race.

Louisiana District 5: March 20 initial vote, April 24 runoff

This contest will fill the seat of Luke Letlow, a Republican who died December 29, 2020, from Covid complications. It’s a Republican-leaning district that is expected to choose another conservative representative. The timing and rules are the same as in District 2. Luke Letlow’s widow, Julia Letlow, has been endorsed by Trump.

Here’s some background on the race.

Texas District 6: May 1 initial vote, May 24 runoff

This contest will fill the seat of Republican Representative Ronald Wright, who died from Covid complications. The suburban district has voted Republican in the past but is trending toward the Democrats. Trump only beat Biden by three points here. The field of candidates is crowded (10 Democrats, 11 Republicans, a Libertarian, and an independent) and a runoff between the top two finishers in the initial vote is likely. This is a district where Pelosi and the Democrats could conceivably pick up a seat, though the late congressman’s widow, Susan Wright, is seen as a strong Republican contender.

Here’s a backgrounder on the race as it stands now. 

Soon to be scheduled

New Mexico District 1, which Haaland won with over 58 percent of the vote in both 2018 and 2020. Some analysts say this seat could be competitive. but Democrats have the advantage.

Here’s some background on the race.

Ohio District 11 (Fudge’s seat), which is a solidly Democratic district in the Cleveland area. Among the announced contenders is former state Senator Nina Turner, a leading supporter of Vermont Senator Bernie Sanders who has attracted major endorsements from progressive leaders and unions. State Representative Emilia Sykes, the minority leader in the Ohio House, is also one of the many Democratic contenders.

Here’s some background on the race.