down to the wire

やはり、大統領選の話題が持ちきりです。
以下のサイトは先ほど私が載せたのと同じ記事でしたが、見出しが異なったのでそこから拾いたいと思います。
down to the wireの部分です。イディオムでgo, come, be (right) down to the wireの形で、" if you say that a situation goes down to the wire, you mean that the result will not be decided or known until the very end." (OALD)とありました。競馬のゴールの針金から来ている表現で、レースの結果が最後までわからないギリギリの戦いが思い浮かびますね。
つまり、「最後の一瞬まで分からない選挙」であることが分かります。(Minnesota)

U.S. election down to the wire as voting begins

Washington (CNN) -- A roller-coaster ride of an election campaign, buffeted by a superstorm and missteps on both sides, finally concludes Tuesday when America decides if President Barack Obama gets a second term or Republican challenger Mitt Romney will move into the White House in January.

In a contest reflecting the nation's deep political chasm, Obama and Romney ran dead even in final polls that hinted at a result rivaling some of the closest presidential elections in history.

The outcome will influence the direction of a government and country facing chronic federal deficits and debt as well as sluggish economic growth in the wake of a devastating recession and financial industry collapse that confronted Obama when he took office as the first African American president in January 2009.

Voters also will determine the makeup of a new Congress, choosing all 435 members of the House of Representatives and 33 of the 100 senators. Analysts expect Republicans to maintain control of the House and Democrats to keep their narrow advantage in the Senate.

http://worldnews.freshgists.com/2012/11/us-election-down-to-wire-as-voting.html