The nation is just past halftime in the 2018 primary election cycle. Twenty states with a majority of House districts, 228 of the total 435, have held their primaries, and all but the three with runoffs have chosen their Republican and Democratic nominees.

The latest results, taken together with the generic ballot — polls asking which party’s House candidate you’ll vote for — tend to undercut the many gleeful predictions of a blue wave that produces a big Democratic majority in the House and perhaps the Senate as well.

The RealClearPolitics average of recent polls shows the Democrats’ lead over Republicans on the generic vote declining from a 13-point margin (49 percent to 36 percent) last December to a three-point margin (43 percent to 40 percent) going into Tuesday’s primaries. Given Democrats’ disadvantage of having so many of their voters clustered in heavily Democratic seats, that suggests a statistical tie. That would mirror the CBS News estimate of 219 seats for Democrats and 216 for Republicans, with a plus or minus 9-seat margin of error. Donald Trump’s 44 percent job approval, well above his 38 percent favorable rating in November 2016, points in the same direction.

[Related: Studying midterm voters, GOP strategists ask: What does it mean to 'approve' of Trump?]

Tuesday’s results tend to confirm this. Most closely watched was California, with 53 House seats and where the focus was on the seven seats held by Republicans but carried by Hillary Clinton in 2016. These obvious Democratic targets represent almost one-third of the 23 net gains Democrats need for a House majority.

Both parties got some good news from these seven districts’ results.

Democrats feared that, because of the large number of enthusiastic anti-Trump Democrats running for office, they would be locked out of the jungle primaries in three districts, in which the top two candidates regardless of party go on to the general election. That didn’t happen. Nor do Democrats seem to have nominated many flaky candidates, as parties sometimes do when flocks of enthusiastic newcomers run.

The good news for Republicans is that these districts look less Democratic than they did in November 2016. Hillary Clinton outpolled Donald Trump in all seven districts then, but this time Republican candidates got combined majorities of 53 percent to 63 percent in six of the seven. And in the seventh, the total Democratic lead was just 51 percent to 48 percent.

More good news for Republicans: They won’t suffer from a lockout in the top statewide race, as in 2016, but will have a candidate contesting the governorship. John Cox will be on the ballot this November. And although there’s time for opinion to shift, past jungle primary results in California, Washington and Louisiana have been good indicators of the vote in November.

Issues can make a difference too. Voters in the intersection of Orange, Los Angeles and San Bernardino Counties overwhelmingly (by an 18-point margin) recalled a Democratic state senator who had voted for a gas tax increase, and installed a Republican in his place. In the overlapping 39th Congressional District, vacated by veteran Republican Ed Royce and considered a prime target by Democrats, Republicans outpolled Democrats by a ten-point margin.

Writing before Tuesday on the left-wing Daily Kos blog, Daniel Donner argued that in 2017-2018 state and special elections, “Democratic overperformance is concentrated in red states and districts that shifted red in 2016” — places where non-college graduate whites gave Donald Trump higher percentages than more conventional Republicans.

In other words, those results look more like the divisions that have prevailed in all but two off-year cycles starting in 1994. Similarly in Tuesday’s primaries, California’s seven Clinton/Republican districts, with high percentages of college-graduate whites and/or Hispanics, swung away from Trump in 2016 — and seem to have swung some distance back to the 1994-2014 norm this year.

This would be in line with polling that shows Donald Trump to enjoy almost universal job approval among self-identified Republicans—higher than all but one post-World War II president enjoyed at this stage in their tenure from his fellow partisans.

The 1994-2014 partisan divisions have been unusually long-enduring, aside from the short-lived shift to Democrats in 2006-08, and the actual number of Obama/Trump voters that switched 100 electoral votes to the Republican was small by historic standards.

Will a reversion to that norm give Republicans a narrow House majority once again this year? That’s one result — though certainly not the only one — that would be consistent with the primary results we’ve seen so far. Opinion can shift: perhaps another blue wave is building. But the one almost everyone was expecting six months ago seems to have crested and ebbed.