Booker may actually be telling the truth (wow a democrat telling the truth... rare thing these days). He could have his eyes on a leadership position once Durbin leaves (probably) in 2020. Him being in the leadership could propel him into the national spotlight and prop up a future Presidential bid.
But then he's open to being president, no?
Anyway, Booker certainly seems interested, by his actions. If he's not interested, then is it just a coincidence that he joined the Foreign Relations Committee this year (a common stepping stone to a presidential run)? And why did he give an interview to a New Hampshire TV station earlier this month? Why did he meet with both the Iowa and New Hampshire delegations at the DNC last year, and even gave an interview in which he said that he’d “fallen in love” with New Hampshire? And is it just a coincidence that he did campaign events for Clinton last year in Iowa, New Hampshire, and South Carolina?