TOKYO, Nov 4 (Reuters) - Japanese government bond prices were mostly higher on Friday as anxiety over the tightening U.S. presidential race hit Tokyo shares and enhanced the appeal of safe-haven debt.

Caution over the U.S. non-farm payrolls report due later in the day limited the JGB market's gains.

The benchmark 10-year JGB yield was unchanged at minus 0.065 percent, while the 30-year yield fell a basis point to 0.475 percent. The 40-year yield was also down a basis point, at 0.565 percent.

Japan's Nikkei fell to a 2-1/2-week low on Friday morning after major stocks like automakers stumbled on continued uncertainty surrounding next week's U.S. presidential election.

Investors have been unnerved by signs the presidential race between Democrat Hillary Clinton and Republican Donald Trump is tightening, after Clinton had until recently been thought to have a clear lead.

(Reporting by the Tokyo markets team; Editing by SImon Cameron-Moore)