Former Irving Mayor Beth Van Duyne is leading Democrat Candace Valenzuela in their race for the open seat in the 24th Congressional District which includes parts of Tarrant, Dallas and Denton counties.
The seat was left open when Republican Kenny Marchant retired.
Early this morning, Van Duyne had 48 percent of the vote while Valenzuela has just over 47 percent.
Three other challengers have each taken at least one percent of the vote.
With many votes still being counted, there is no clear winner yet.
