When it finally became clear that President Donald Trump’s challenges to the election results weren’t going to change a single vote, Republicans had to accept a stinging defeat and pin their hopes on taking back Congress in 2022.

This seemed to be a reasonable objective, and it helped take the sting out of the loss. After all, Trump’s defeat overshadowed the fact that Republicans nearly won back the House in 2020. And despite suffering a double-punch loss to the hard-left duo of Rafael Warnock and Jon Ossoff in the Georgia Senate races, Republicans entered this year only one Senate seat away from regaining power in the upper chamber.

But around every silver lining is a dark cloud, and there are some ominous signs that could make the 2022 midterms yet another painful political cycle for Republicans. For one, there’ll be some noteworthy GOP senators retiring. And while holding onto a seat held by an incumbent is statistically favorable, filling a seat after a retirement is a challenge for either party.

One of the more noteworthy Republican retirements will be that of Missouri Senator Roy Blunt. As The Dispatch reports, “Blunt has been in Congress for a while — 14 years in the House, and 10 in the Senate — and held leadership roles in both chambers. He’s long been one of Mitch McConnell’s closest allies, and was considered a potential successor to the minority leader by some. Not anymore.”

The Dispatch adds, “The biggest difference between 2010 and 2022 is that the GOP’s polarizing ex-president is adamant on playing a large role in the midterms this time. That likely won’t matter in states like Alabama, Missouri, and Ohio — which Trump won in November by 25, 15, and 8 percentage points, respectively — but nominating a Trump acolyte could make things tricky for Republicans in Pennsylvania and North Carolina.”

Kentucky Senator Mitch McConnell remains influential, but even he, fresh from being reelected to yet another six-year term, isn’t guaranteed to finish out his current one. After all, McConnell is 79, and he’s had some health problems in recent years.

Some Republican Kentucky legislators are putting a mechanism in place to fill McConnell’s seat should it become vacant. Senate Bill 228 would allow an executive committee of the party holding the Senate seat to provide a list of three names rather than empowering the Democrat governor to choose a successor.

McConnell supports Senate Bill 228 “because of the razor-thin margins in the U.S. Senate,” writes Nick Storm of The Intercept. “For those Republicans, McConnell is seeking to protect the upper chamber from adding an additional Democrat.”

Other senators who’ve already announced their retirements include Ohio’s Rob Portman, North Carolina’s Richard Burr, and Pennsylvania’s Pat Toomey. All three are only in their 60s but claim to have grown disenchanted with the partisan nature of Senate politics in recent years. Chuck Grassley, who’s 87, continues to mull over his options and won’t make an announcement until the fall. Several other Republican senators have yet to make a commitment to defending their seats.

In most years, the enthusiasm of Republican voters would be a reliable factor to consider, but a recent poll reveals that GOP voters are still simmering over what they perceive to have been a capitulation by party leaders in the Senate — both for having accepted Joe Biden’s electoral victory and for their criticism of Donald Trump.

Even with history on their side (the party out of power usually picks up seats in the midterms), it appears that the unpredictable outcome of the 2022 races will be the only thing Republicans can count on.