*Updated to include a candidate whose filing was not initially reported by the secretary of state's office.

Twenty-seven candidates have filed for a trio of Nov. 5 special elections to fill state House seats, including one that Democrats are aiming to flip, according to the secretary of state's office.

The filing deadline was 5 p.m. Wednesday.

The most closely watched contest will be in House District 28, where Rep. John Zerwas is stepping down at the end of the month to join the University of Texas System. The Richmond Republican won reelection last year by 8 percentage points, and Democrats were already targeting HD-28 as they push to capture the House majority next year.

Democrats in HD-28 have coalesced around Elizabeth "Eliz" Markowitz, who was the only Democrat to file. Markowitz, a Katy teacher, unsuccessfully ran last year for State Board of Education District 7, which overlaps with HD-28.

Six Republicans, meanwhile, filed for the seat, making it likely that there will be a runoff featuring one of them and Markowitz, who will not have to split the Democratic vote. The GOP contenders are:

Anna Allred, a Houston anesthesiologist from the same doctor group as Zerwas

Gary Gates, a Rosenberg businessman who has unsuccessfully run for several other offices, most recently railroad commissioner in 2016

Gary J. Hale, a Katy business owner who has his own intelligence firm and is a retired intelligence official with the Drug Enforcement Administration

Tricia Krenek, a Katy attorney and former member of the Fulshear City Council

Sarah Laningham, a Richmond woman who works in sales and unsuccessfully ran for House District 14 in 2018

Clinton D. Purnell, a Katy man who works in logistics and customs compliance

The other two special elections are happening in safely Democratic districts, though they too have drawn large fields that all but guarantee runoffs. In House District 148, 15 candidates — 12 Democrats, two Republicans and one independent — filed to succeed Houston Democratic Rep. Jessica Farrar, who like Zerwas, is leaving the House on Sept. 30. In House District 100, five Democrats have lined up to replace former Rep. Eric Johnson, D-Dallas, who vacated the seat earlier this year after winning the Dallas mayoral race.

The HD-100 candidates:

James Armstrong III (D)

Lorraine Birabil (D)

Daniel Davis Clayton (D)

Sandra Crenshaw (D)

Paul K. Stafford (D)

The HD-148 candidates:

Rob Block (D)

Kendra Yarbrough Camarena (D)

Chris Carmona (I)

Carol Denson (D)

Anna Eastman (D)

Adrian Garcia (D)

Terah Isaacson (D)

Michele Leal (D)

Ryan McConnico (R)

Mia Mundy (D)

Anna Núñez (D)

Luis La Rotta (R)

Penny "Morales" Shaw (D)

Alva Trevino (D)

Chris Watt (D)

Early voting starts Oct. 21 for the special elections.

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