With a week to go before the election, the total spent on the U.S. Senate race in Alaska is already in the $50 million range, far surpassing any election in state history.

The campaigns and outside groups chipping in tens of millions to to help or hinder Sen. Mark Begich and challenger Dan Sullivan are on track to spend $150 to $200 per vote.

The nonpartisan Center for Responsive Politics shows $37.7 million has been spent by outside groups, while the Federal Election Commission says Begich has spent $7.6 million and Sullivan has spent $6.7 million.

The term "outside spending" does not refer to spending Outside, as in anywhere but Alaska, but to groups that are not officially connected to the candidates.

These include national party committees, super political action committees and groups that raise money but don't disclose their donors.

Nationwide, spending by outside groups in this election cycle has been $479 million, the Center for Responsive Politics says.

In Alaska, the Senate race has dominated the political landscape for months because of the cash infusion from groups waging the battle for Senate control.

If 250,000 people vote in the Alaska race, roughly the same as the total votes cast in the 2010 Senate race, $50 million works out to $200 per vote.

In 2012, there were 300,000 voters, but turnout is usually higher for presidential elections. Alaska has about 509,000 registered voters.

In 2010, when Sen. Lisa Murkowski won on a write-in campaign against Republican Joe Miller and Democrat Scott McAdams, outside spending in the 2010 contest totaled about $4 million.

This year, with more than nine times as much being directed to Alaska, more than $19 million has been in support of Begich or against Sullivan, while $17 million went to support Sullivan or oppose Begich. The figures are incomplete, however, because some groups do not have to report what they spend on ads run early in the campaign that appear to back or oppose a candidate, but stop short of a clear declaration.

The statistics show that the outside spending in Alaska is the fourth highest in the country, not in per capita terms, but in total dollars spent. In per capita terms, it is the highest.

The North Carolina Senate race tops that list with outside spending of $72 million, followed by Colorado with $60 million, Iowa with $55 million and Alaska with $37.7 million.

Arkansas, which is fifth with spending of $37.3 million, has about 1.7 million voters, more than three times the number in Alaska. Total spending on the Senate race there between Democratic Sen. Mark Pryor and Republican Rep. Tom Cotton has reached $57.9 million, according to the Institute for Southern Studies. That works out to about $34 per registered voter. In Alaska, the Senate race spending has already topped about $100 per registered voter.

In North Carolina, where Democratic Sen. Kay Hagen is battling Republican Thom Tillis, the total spending is about twice as much as in Alaska. However, the amount per registered voter spent in that race is about $13. There are 6.6 million voters in that state.

Of the major groups in the Begich-Sullivan race, Put Alaska First, the super PAC backing Begich, has spent more than $9 million, while the National Republican Senatorial Committee has spent more than $4 million for Sullivan. The Democratic Senatorial Campaign Committee has spent $3.7 million on behalf of Begich.

American Crossroads has spent more than $4.2 million and Crossroads GPS has spent $2.7 million to assist Sullivan.