(New York) The chips are down, as they say in Las Vegas. Since Nevada’s June 11 primary, both major U.S. parties have chosen their key candidates for the U.S. Senate, with 34 seats (out of 100) up for grabs in November.

At this point, the oddsmakers are giving little credit to the Democrats, whose majority rests on their control of 51 seats. The reason is very simple: candidates from Joe Biden’s party or their independent allies must defend a total of 23 seats. Twenty-three seats, three of which are in states where Donald Trump easily beat Joe Biden in 2020 and five in key states where he enjoys a more or less significant lead in the polls over the Democratic president.

We might as well say that it would take almost a miracle for the Democrats to maintain their majority. The stakes are not small. Donald Trump notably promised to choose even younger and more conservative judges than those he has already appointed for life to the Supreme Court, if he returns to the White House with a Republican majority in the Senate. The upper house of Congress, it should be remembered, has the responsibility of confirming or rejecting the choices of presidents to the highest court in the country.

However, no offense to the bookmakers in Las Vegas, the battle for the Senate involves a mystery in 2024.

Take the case of Nevada. According to the RealClearPolitics (RCP) site poll average, Donald Trump leads Joe Biden by 5.3 percentage points in this state which has not voted for a Republican presidential candidate since George W. Bush.

However, in the Silver State’s Senate race, Democratic Sen. Jacky Rosen enjoys a 4.6 percentage point lead over Republican candidate Sam Brown, according to RCP’s polling average.

It should be noted that Sam Brown is nothing like a Herschel Walker or a Mehmet Oz, these Republican Party senatorial candidates whose ineptitude appeared obvious to everyone, except Donald Trump, their selector and promoter in 2022 A veteran of the war in Afghanistan, this man survived horrific injuries that left him disfigured before achieving some success in business.

In Pennsylvania, the state where the 2024 presidential election could well be played out, outgoing Democratic senator Bob Casey has a 5-point lead over his Republican rival, businessman David McCormick, according to the RCP poll average .

However, in the same state, Donald Trump is ahead of Joe Biden by 2.3 percentage points.

How do we explain the fact that Democratic Party senatorial candidates are doing much better in key states than Joe Biden in the polls?

First answer among many: For the moment, the Democratic incumbents in these states are much better known than their Republican rivals, with the exception of Arizona Democratic Representative Ruben Gallego and his Michigan colleague Elissa Slotkin.

And what could be the consequences of this phenomenon on the 2024 presidential election?

Before answering that question, a reminder: The days when voters could vote for one party’s candidate for president and another party’s candidate for senator or representative appear to be over. In 2020, only one state — Maine — made a different partisan choice for president (Joe Biden) and Senate (Susan Collins).

As for the presidential election, this reality can turn out to be good or bad for each candidate, depending on the scenario that prevails. Current polls may be underestimating Joe Biden’s support.

On the other hand, voters in the same states may want to be consistent with their current preferences in the race for the White House and vote en bloc for the senatorial candidate from Donald Trump’s party.

Which scenario will prevail? This is the mystery of the Senate battle. A mystery wrapped in an enigma. Because outgoing Democratic senators Jon Tester and Sherrod Brown are also ahead of their Republican rivals in the red states of Montana and Ohio, according to RCP polling averages.

Only West Virginia, whose current senator, Joe Manchin, has announced his retirement, is sure to fall into Republican hands. And even then, a surprise is not impossible.

On May 31, Joe Manchin changed his political allegiance, leaving the Democratic Party to become an independent. The change could theoretically allow him to defend his old Senate seat as an independent or even run for governor of the state, a position he has already held. He has until August 1 to tune in.

In short, the game is perhaps not yet made.