Dem
47
GOP
53
All his life Donald Trump has done something out of Franklin D. Roosevelt's playbook: pit people against each other. For FDR, it was assigning a task to, say, the Department of the Interior and to the Department of Agriculture, and seeing which one got it done first (or better). For Trump, it is the succession: J.D. Vance or Marco Rubio? The very existence of a discussion about the succession means Trump understands he cannot have a third term, so he wants the next president to cement his legacy. He has been asking people around him for a preference and it is Rubio by a country mile. Vance acts like he is next in line, but he is an obnoxious opportunist without a lot of real friends.
Trump is very superficial and consumes a lot of news. Rubio has a real job (actually, several of them) and is in the news all the time, especially with conflicts all over the world, which is the secretary of state's natural bailiwick. Rubio is also NSA. In contrast, the veep has no real job unless: (1) the Senate is tied 50-50 or (2) the president assigns him something to actually do (which Trump hasn't). So Rubio can get on TV whenever he wants to by announcing that he is negotiating with someone about something.
Playing the two against each other doesn't mean Trump is about to endorse either one for president. That will have to wait until the 2028 race heats up, which won't be until the fall of 2027, when the first debates will be held. If both of them declare a run, Trump could watch the debates and decide which one looks better on the tube, and take it from there.
Many donors and Republican operatives prefer Rubio because he doesn't have the sharp edges Vance does. A Vance campaign would be a base-only campaign. He is Trump without any of the charisma that some independents like. He is straight-up nasty and will get roughly 0% of Democratic votes and few independent votes. Rubio is much softer and less abrasive. He can probably get some normie Republicans to vote for him in the primaries and independents to vote for him in the general election. He is certainly the stronger general-election candidate, assuming that foreign affairs don't go south now, with Trump heaping blame on him.
From Trump's point of view, there is a bit of a dilemma. Vance will try to continue his MAGA, America First policies. If Rubio wins, he will probably move to the middle and not be true MAGA at all. So Trump can either go with the guy who will continue his policies but is the weaker general election candidate or the guy who will march to his own drummer but is more electable. For this reason, we expect Trump to refrain from endorsing anyone until he has a better idea who is a stronger primary candidate and who is a stronger general-election candidate, and that won't be until late 2027. Both Vance and Rubio are smart enough to realize this, so they have to continue to act like buddies until the show really gets going in maybe 18 months.
Historically, sitting veeps rarely get elected as president. The last one to pull it off was George H.W. Bush. The last one to fail at it was Kamala Harris. The problem is that the veep is closely tied to the president, and only if the president is very popular does that work, and then not always. Bill Clinton had a 68% approval rating toward the end of his term but that wasn't enough to get Al Gore over the finish line. Vance is going to be joined at the hip with the unpopular Trump. Rubio, much less. Of course, if the world is in flames in 2 years, Rubio will get some of the blame that an outsider, say Gov. Brian Kemp (R-GA), will not. (V)