There are many parallels between Sukkos and Chanuka:

 - The Gemara in Shabbos 21b gives an explanation for Beis Shammai's
   opinion that one should count down candles throughout Chanukah that
   it's just like the karbanos of Sukkos which also counted down.
 - The latest time to bring Bikkurim is Chanukah, and the latest time,
   according to the Tanna Kamma, to say the accompanying passages is
   Sukkos (Bikkurim 1:6).
 - The Haftarah of the second day of Sukkos is that of the Chanukas
   HaBayis, paralleling the Chanukas HaMizbeiach of Chanukah. Remember,
   we say Mizmor Shir Chanukas HaBayis throughout Chanukah after
   Shacharis.
 - Chagai (Perek Beis) received a nevuah on Hoshanah Rabbah concerning
   Galus Yavan.
 - Both a Sukkah (Sukkah 2a) and a Menorah (Shabbos 22a) must be less
   than 20 amos tall.
 - Maccabim 2:10:9-10 records that the eight days of
   Chanukah paralleled those of Sukkos, and they took Aravos and Lulavim
   to celebrate the neis that occurred.

Why are there so many parallels between Chanukah and Sukkos?