PHOENIX -- The air war in Arizona's Senate race is continuing to escalate.
The National Republican Senatorial Campaign Committee is dropping another $2.3.million on the race as polls show Republican Jeff Flake and Democrat Richard Carmona are running neck and neck.
Politico first reported late Tuesday that the NRSC used the cash to buy up commercial time during the remaining two weeks of the election.
The money adds to the impressive amount outside groups have already spent on both candidates in this high-stakes political battle. According to the Center for Responsive Politics, outside groups have doled about $3.5 million on Carmona.
Various organizations had spent about $5.4 million on Flake, according to the online finance records. The additional $2.4 million would raise Flake's total to $7.8 million between the primary and general elections.
Supporters of Carmona were quick to jump on the news, pointing to it as evidence Flake is in trouble. Carmona's campaign released an internal poll early Tuesday showing Flake trailing by 4 points.
Flake supporters rejected the survey, saying it couldn't be trusted because Carmona paid for it. However, there has been very little independent polling in the race as both campaigns have released polls showing themselves in the lead.
The hard-hitting ads between Carmona and Flake have already saturated the Valley airwaves and brought in millions of dollars to local television stations.
At the start of the race, the odds were that Flake would walk away with the first open Arizona Senate seat in 18 years. But as the race appeared to tighten, the stakes continued to get higher.
This is now being watched by politicos across the country as the outcome could determine the balance of power in the U.S. Senate.
Democrats currently hold the majority, but Republicans are hopeful they can take it back. A Carmona win would likely kill any Republican chance of making that happen.