Complex sentence: Eolis has since been involved in politics first in Giuliani's initial Mayoral campaign, then, after his first election on his transition team and later as an advisor in City Hall operations, including: communications, law department, and personnel matters.
Split into simpler sentences: Eolis has since been involved in politics, first in Giuliani's initial Mayoral campaign. She was part of his first transition team and later advised him on City Hall operations, including: communications, law department, and personnel matters.