TOKYO, July 21 (Reuters) - Japanese Prime Minister ShinzoAbe's Liberal Democratic Party and its junior coalition partner,the Komeito party, look set to retain a solid majority inparliament's upper house in Sunday's election, media surveysshow.
Up in the air, however, is whether the ruling bloc, alongwith the smaller Japan Innovation Party and independents, willkeep the two-thirds majority necessary for Abe to have a chanceof achieving his goal of revising the pacifist constitution.
Below are key facts about the upper house election andimportant numbers to watch.
WHAT IS THE UPPER HOUSE?
The upper house is the less powerful of parliament's twochambers. It lacks the authority to select a prime minister, andbudgets and treaties can be enacted without its approval.
But the chamber can reject other bills approved by the lowerhouse, and the legislation can then only be enacted by atwo-thirds majority of the lower chamber. Abe's ruling blocholds a two-thirds majority in the lower chamber.
The number of upper house seats will increase by three to245 after Sunday's election, when 124 of the seats will be upfor grabs. The total number of seats will be raised by anotherthree to 248 in three years, when the next upper house electionis held.
HOW THE ELECTION WORKS
Of the 124 seats at stake, 74 are for prefectural orprovincial constituencies, each with one to six seats, wherecandidates with the most votes win. Another 50 seats are from anationwide proportional representation bloc, where voters chooseeither a candidate or a party, and seats are allotted based onthe total number of votes cast for parties and their candidates.
FIFTY-THREE, SIXTY-THREE, EIGHTY-FIVE
Abe's ruling bloc holds 70 seats that are not up forre-election, and therefore needs to win 53 of the 124 seatsbeing contested to maintain a majority, his stated target.
The Liberal Democratic Party (LDP) and the Komeito partyneed to obtain a combined 63 seats to win more than half of theseats in contention and tighten their grip on power.
The ruling bloc, coupled with the Japan Innovation Party andindependents who are open to constitutional revision, hold 79uncontested seats, and need to take 85 seats on Sunday to keep atwo-thirds majority, according to media calculations.
A constitutional revision requires approval by two thirds ofboth chambers of parliament and a majority in a publicreferendum. The pro-revision camp holds a two-thirds majority inthe lower house.(Reporting by Kiyoshi TakenakaEditing by Robert Birsel)