FACTBOX: Leaders of Japan's two main political parties

(Reuters) - Japanese Prime Minister Shinzo Abe's conservative ruling coalition lost its upper house majority in elections on Sunday, but the 52-year-old conservative said he intended to stay on in his post.

The main opposition Democratic Party of Japan was on track to become the biggest party in the upper chamber.

Following are some facts about Abe and Democratic Party leader Ichiro Ozawa.

SHINZO ABE

* Born in 1954 and a third-generation politician, Abe is Japan's first prime minister born after World War Two. He has made revising the U.S.-drafted postwar pacifist constitution and boosting Japan's security profile key planks of his platform.

* His grandfather, Nobusuke Kishi, was a wartime cabinet minister who was imprisoned after the war but never put on trial. Kishi served as prime minister from 1957 to 1960 and had a strong influence on the young Abe.

* Abe's support ratings have sunk to around 30 percent, which some analysts consider a crisis level, on voter outrage over bungled pension records and concern about political corruption.

* The soft-spoken Abe is known for his stylish clothes and a sweet tooth. He and his wife Akie, 45, have no children and Akie has said the couple has fertility problems.

ICHIRO OZAWA