ATLANTA (AP) — The two Republicans vying for Georgia's open Senate seat have spent a combined $11 million so far on the race, with just over a week to go before the July 22 runoff.

Rep. Jack Kingston has dominated in fundraising throughout the campaign, although former Dollar General CEO David Perdue has been closing the gap helped in large part by his personal funds.

On Thursday, Kingston reported receiving $1.6 million in contributions over the past two months, compared to $974,000 in contributions for Perdue.

The race is among a dozen being watched nationally as Republicans seek control of the Senate. Democrats are hopeful their candidate Michelle Nunn, the daughter of former Sen. Sam Nunn, will be able to claim the Georgia seat and help them keep a majority in the Senate.

Nunn is considered among the best Democratic recruits this year and has also posted strong fundraising numbers.

Among the Republicans, Kingston began his campaign with a large cash advantage. He had about $2.3 million in his congressional campaign account that was transferred over for the Senate race.

Perdue, who made millions overseeing companies including Dollar General and Reebok, has pumped $3.1 million of his own money into the race through a combination of loans and personal contributions.

The latest was a $500,000 loan made sometime over the past two months, according to his campaign report. Those funds have helped Perdue keep pace with Kingston, who has earned the backing of the U.S. Chamber of Commerce and two former rivals in the Republican Senate race.

With just over a week to go before the runoff election, Kingston holds an edge in terms of cash on hand, with about $1.2 million. Perdue had about $783,000 in the bank to start July.

Overall, Kingston has raised nearly $5.3 million in contributions to Perdue's $4.6 million, which also includes $1.9 million of his own money.

Nunn has yet to release her latest fundraising report, which isn't due until this week.

Beyond the candidates, the race has drawn more than $7.8 million in spending by outside groups. According to Federal Election Commission data, that total puts the Georgia race behind Senate contests in just three other states: Mississippi, North Carolina and Massachusetts.

Kingston is at the center of much of the outside spending, both as the beneficiary and the target.

The U.S. Chamber of Commerce has plowed $2.3 million into three separate statewide TV ads backing Kingston, with $1.4 million during the runoff.

A PAC backing Perdue, meanwhile, has reported more than $2 million in spending, nearly all of it on ads attacking Kingston.

Last week, Nunn challenged Perdue and Kingston to swear off any third-party help but the pledge was only good if her Republican opponent agreed.

Neither accepted, and it would be impossible, in any case, for a candidate to block an independent group from participating in a race because candidates are not allowed to coordinate with such groups.

The broader idea, however, has gained some traction since 2012, when Democratic challenger Elizabeth Warren and then-Sen. Scott Brown, a Republican, agreed to make a charitable donation from their campaign accounts when an outside group spent money in their race.

Warren defeated Brown, who is now running for the Senate in New Hampshire.

Also on the November ballot in Georgia is Libertarian Amanda Swafford, a former Flowery Branch councilwoman.