Dem
51
GOP
49
In 2022, then-chairman of the NRSC, Sen Rick Scott (R-FL), decided not to intervene in Republican primaries and let the voters decide. The voters (with some help from Donald Trump) picked a bunch of nuttier-than-a-fruitcake candidates in key races, most of whom went on to lose. This time, the NRSC appears ready to intervene early in primaries to get the establishment's preferred candidate nominated.
The first piece of evidence for this changed policy comes in Indiana. Sen. Mike Braun (R-IN) is retiring to run for governor, leaving an open seat behind. At first, it looked like former Indiana governor Mitch Daniels (R) was going to jump in. In the end, he decided not to. Immediately after his decision, the NRSC endorsed Rep. Jim Banks (R-IN), in an attempt to clear the field and avoid a super Trumper from getting in and winning the nomination. Banks is Trumpy enough, but at least he is a sitting member of Congress and not some weirdo outsider. Trump himself has endorsed Banks, so maybe this time the establishment and Trump agree on the candidate. That may not always be the case, though.
There are multiple other states where Republican Senate primaries are likely. In West Virginia, Rep. Alex Mooney (R-WV) is already in, but Gov. Jim Justice (R-WV) is exploring a run, as is AG Patrick Morrisey (R). Will the NRSC interfere here? Montana now has two representatives—and both of them want to get out of the House and into the Senate. Again, will the NRSC pick sides? And there is Arizona, as discussed above.
Ever since 2014, the NRSC has stayed out of primaries. While picking a candidate has an upside (the Party doesn't have to defend some wacko in the general election), it also has a downside. The downside is that if the NRSC tries to defeat some primary candidate and that candidate wins primary anyway and is elected, the Party will have no control of the candidate in the Senate and he or she will do whatever he or she wants to. The Republicans really don't want any more copies of Sen. Rand Paul (R-KY). (V)