Japan's governing party is meeting to vote in a leadership election that could give the country its third prime minister in a year.

日本执政党正在集会举行领导权选举，该选举将会使日本在一年之内产生第三位首相。

Ichiro Ozawa (L) and Naoto Kan (R) disagree on how to manage the economy

Veteran power-broker Ichiro Ozawa has challenged Prime Minister Naoto Kan for the top job in the wake of poor results in July's upper house elections.

Reports from Japan suggest that the race is too close to call.

Mr Kan is more popular with the public than his rival, but Mr Ozawa commands support from a large party faction¹（派别，内讧） .

The Democratic Party of Japan's (DPJ) 411 members of parliament, local DPJ lawmakers and party members will choose between the two men on Tuesday afternoon.

Both men will speak for 15 minutes before lawmakers cast their ballots².

Reports suggest MPs - whose votes carry much more weight - are evenly split between the two men, while Mr Kan has more support from local lawmakers and party members.

Whoever becomes party leader will become the prime minister, because the DPJ has a majority in the lower house of parliament.

The power struggle comes as Japan battles with a sharp rise in the yen³, which is damaging exports. On Tuesday the dollar fell to a 15-year low against the yen in early trading.

Economy key

On Monday, the leadership rivals visited undecided lawmakers and party groups in a last-minute bid to secure support.

Naoto Kan has only been in power for three months.

He was elected after Yukio Hatoyama stepped down over failing to follow through on a promise to move an unpopular US military base from the island of Okinawa.

Weeks after Mr Kan took power, the DPJ lost seats in upper house elections - a result blamed in part on his stance on raising consumption tax（消费税） .

Mr Kan has said he believes the tax should be raised and spending curbed⁴ in a bid to reduce Japan's massive public debt.

Mr Ozawa, who announced his leadership challenge in August, is widely seen as the architect of the DPJ's election victory in August 2009.

He stepped down as deputy party leader in May 2009 amid a funding scandal and has since become embroiled⁵ in（卷入） a second one relating to a land deal.

But he had remained a major DPJ power behind the scenes.

He has promised to follow through on DPJ spending pledges and says he would consider more borrowing.

Mr Ozawa has also suggested that the controversial deal to relocate the unpopular Futenma US military base from central to northern Okinawa could be reviewed.