A few months ago, we explored the huge and growing partisan gender gap on Capitol Hill. There are nearly three times as many Democratic women in Congress as Republican women. We found four likely causes for that gender gap:

A lack of GOP women in the congressional “pipeline,” such as women serving in state legislatures. Republicans, unlike Democrats, have not made electing women a priority. Republican women face particular hurdles in GOP primaries, such as being perceived as more moderate than Republican men. And many of the Republican women who do win opt to leave Congress fairly soon after being elected.

So we floated one idea to close the gap: The GOP establishment could encourage strongly conservative women to run in red states. That way, they’d be set up to win the primary and the general election.

But looking at what happened last night in Tennessee shows why it may take a long time before we see a significant increase in the number of Republican women in Congress (and in other key political posts). The Volunteer State could have nominated a Republican woman for governor and U.S. senator — if they went on to be elected, they’d be the first women from either party to hold those offices in the state. Instead, 2018 could result in a decline in high-profile female representation in Tennessee.

Diane Black and Marsha Blackburn, both former Tennessee state legislators, had already gotten to Congress, currently serving as two of only 23 GOP women (among 236 total Republicans) in the House. Both sought promotions this year — Black ran for governor, Blackburn for the Senate.

Blackburn overwhelmingly won, by about 69 percentage points, the Senate primary last night against long-shot opposition. The longtime congressman (she prefers to be described as a congressman) was certainly well-positioned for this run, with a deeply conservative record and reputation. Some people in the GOP establishment in Tennessee were wary of Blackburn, but Republicans at the national level helped her candidacy along. A group called Winning For Women, which is raising money for female GOP candidates (borrowing from the model of Emily’s List on the Democratic side), got behind Blackburn last fall. Earlier this year, when U.S. Sen. Bob Corker (whose seat Blackburn is running for) was reconsidering his decision to retire, Trump and other national GOP officials refused to get behind him, with the president reportedly calling Blackburn personally and encouraging her to keep running. Corker, facing a potentially difficult primary race against Blackburn, backed down, and Trump formally endorsed Blackburn in April.

So in Blackburn’s case, I would argue Republican Party officials are doing basically everything they can to help her get elected to the Senate. But they got unlucky: Democrats managed to convince a popular former Tennessee governor, Phil Bredesen, to run for the seat. I doubt many Democrats could make Tennessee competitive. Bredesen is different. He has led in most of the polls that pit him against Blackburn and has a good chance of winning.

Black was a different case. She finished third in the gubernatorial primary on Thursday (businessman Bill Lee finished first). She had some, but not full, party support. Vice President Mike Pence endorsed Black, and Trump said some nice things. But Trump never formally endorsed her. (In contrast, Trump sent out a tweet backing Georgia gubernatorial candidate Brian Kemp that Kemp says was a big factor in his primary victory last week.)

Why didn’t Trump get behind Black? He might have heeded the advice of outgoing Tennessee Gov. Bill Haslam, who urged the White House to stay neutral in the GOP gubernatorial primary. But I think it’s more likely that the administration didn’t care what Haslam wanted (after all, Pence did endorse). Instead, I’d bet that the White House wasn’t sure Black would win even with the president’s backing, and they didn’t want Trump to support someone who then lost.

There’s a third part of the story on gender here — and this is the worst one for the Republicans if they are interested in closing the gender gap on Capitol Hill. With Blackburn and Black running for higher office, there were primaries on Thursday to fill the House seats they would be leaving open. Two men won: Former Tennessee agriculture commissioner John Rose (in Black’s district) and state senator Mark Green (in Blackburn’s district). Unlike Blackburn, Green and Rose are virtually guaranteed to be elected to Congress because these districts are more conservative than the state overall and the Democratic nominees don’t have a history of winning elections in Tennessee like Bredesen does.

It’s not just that male candidates won — there appears to have been little effort to make it possible for Black and Blackburn to be succeeded by other female Republicans. I haven’t extensively studied the process by which candidates were recruited (or not) by GOP officials in either district. But in Black’s district, according to Ballotpedia, only one of the five Republican candidates who formally entered the GOP primary was a woman. She had no experience in elective office and finished fourth in the primary. In Blackburn’s district, Green was unopposed for the GOP nomination.

I think it’s fairly unlikely in the Democratic Party — with its more explicit considerations of gender and race, and the deep involvement of Emily’s List in races across the country — that two House seats previously occupied by women would have gone back to men without a fight.

So, in theory, Tennessee could have come out of 2018 with a Republican woman as U.S. senator, a Republican woman as governor and still two Republican women as House members. Instead, the state will be down two Republican women in the House. Tennessee could still gain a GOP woman in the Senate. But if Blackburn loses, the state would be down to zero women in the House, Senate and governor’s mansion.