For its special election to fill a vacant House seat, Texas used the top-two primary structure currently used more generally in CA and WA. There were 23 candidates who ran, and since no one is going to win an outright majority, there will be a run-off election. This is a competitive congressional seat. Susan Wright (R), the widow of the man who had been elected to the seat, is the plurality winner; it is currently uncertain whether the person who will come in second and make the run-off is another Republican or a Democrat.
There is a debate, among those seeking to reform primary elections to increase the chances that more broadly consensual candidates will get elected, as to whether the top-two structure is the best form for this change or whether a top-four system (as Alaska voters recently adopted) or a top-five system would be better. In a top-two system, it is possible, and happens not infrequently, that two candidates from the same party will be the only ones who make it to the general election — which might happen in this TX race, even though the district is competitive in the general election. The top-four system makes it likely that each party will get at least one candidate through to the general election; Alaska combines this structure with RCV in the general election, to make it more likely the candidate with the broadest appeal will win.
There is a currently a debate, not widely recognized, within the groups that focus on primary-election reforms about which of these options is the best structure for reforming primaries.
Update: Now that the tallies are in, the general election will indeed be between two Republicans. According to the WP story, “Wright and Ellzey, who had challenged Ron Wright in 2018, had no substantive policy differences when compared with the other GOP candidates.” This is a district Donald Trump won by 3 points in 2020.