KIEV, October 27 (RIA Novosti) - President Viktor Yushchenko filed on Tuesday the documents to register as a candidate in Ukraine's upcoming presidential election.

The incumbent leader is unlikely to win the January 17 election, the first since the 2004 "orange revolution" that swept him to power, as polls put his support in the low single digits.

Opinion polls point to Viktor Yanukovych, the president's opponent in the 2004 race, as the leading contender, along with former Yushchenko ally and now rival Prime Minister Yulia Tymoshenko. But pollsters say none of the candidates is likely to garner the 50% plus one vote required to avoid a runoff.

Five people have formally registered as contenders, including Supreme Rada Speaker Volodymyr Lytvyn, ex-defense minister Anatoliy Hrytsenko and Communist leader Petro Symonenko.

The registration deadline is November 9.

Yushchenko addressed his supporters near the Central Election Commission building after he submitted the documents.