I wonder if there’s a strategy behind it or if it’s just a case of a rusty pol not knowing, or maybe not caring, that conservatives want Lynch held up due to her support for Obama’s executive amnesty. Everyone who’s running for president has an interest in seeing nominees expeditiously confirmed; if candidate Jeb comes out for blocking Lynch, President Jeb will be confronted with that precedent later. Jeb is also on record as opposing Obama’s amnesty — albeit mainly because he fears it’ll make it harder for Congress to pass comprehensive reform — so he can always plead “I’m on your side!” to border hawks later, kinda sorta. Even so, Scott Walker, another of the field’s most electable prospects who’s desperate to get right with righties on immigration, called on the Senate to block Lynch for supporting O’s power grab. Granted, he needs to impress conservatives more than Bush does because he’s banking on their votes to help him win the primaries, but Jeb’s going to need the right at some point in this process. Why antagonize them (again) needlessly when Lynch is obviously going to be confirmed anyway, and probably fairly soon given the most recent tea leaves from the Senate? (Harry Reid’s threatening to force a vote if McConnell doesn’t move soon but I doubt it’ll come to that.) He could always spin his opposition later as president by claiming this was a special circumstance where an AG nominee had expressed support for a policy that he thought was unconstitutional and had already been halted by one federal judge. Joining the right on this would have been an easy way to earn some cheap “one of us” cred with a wing of the party that’s deeply skeptical of him. He passed.
The best explanation I can come up with is that Jeb is counting so heavily on outperforming GOP expectations among Latino voters in the general election that he doesn’t want to hand Dems any more ammo to claim, absurd as it may seem, that he’s anti-amnesty. He already went as far out on the limb as he could by denouncing Obama’s executive action, and even there he was careful to say that he supports legislative action as an alternative. Throwing in with tea partiers in blocking Lynch to show that O’s amnesty is somehow intolerable to him might be a bridge too far.