A top communications staffer for Sen. Jeff Sessions, R-Ala., is joining Donald Trump’s campaign to win the Republican presidential nomination.

Stephen Miller is leaving his job as Sessions’ communications director for a position as senior policy advisor for Trump’s campaign, Trump spokeswoman Hope Hicks confirmed to the Washington Examiner. Miller worked for Sessions for seven years, a tenure that saw Miller lead Sessions’ communications team through the effort to stop the Gang of Eight immigration bill that Senator Marco Rubio, R-Fla., helped draft in 2013, a fight that set the terms for much of the GOP primary season.