On Tuesday voters in Arizona's 8th congressional district will go to the polls to cast their votes in the special election to fill the seat left open after former Rep. Gabby Giffords' resignation.

The race, which has been under way since April, is between Republican nominee Jesse Kelly, a former Marine who ran against Giffords in 2010, and Ron Barber, Giffords' former district director. Barber himself was injured in the shooting outside the Safeway grocery store on Jan. 8, 2011. He was shot in the leg and the cheek.

Giffords has not been very present in Barber's campaign. She was featured on a mailer paid for by the Democratic Party of Arizona, and she will be campaigning for the candidate this weekend. However, regardless of Giffords level of involvement, the race was never going to be in the bag for Democrats.

"It's a district that's pretty much split right down the middle, and one of the reasons that Gabby Giffords was able to get elected and re-elected was that she was a more conservative Democrat," said Brinton Milward, director of the National Institute for Civil Discourse, who also directs the University of Arizona's School of Government and Public Policy.

The 8th district, currently located in the southeastern portion of the state and includes part of Tuscan, leans Republican. It has gone red in the past three presidential elections. Giffords narrowly won her re-election in 2010 against Kelly, 30, ultimately defeating him by a margin of about 2 percentage points.

Voting registration figures from the Arizona Secretary of State show a higher number of registered Republicans than registered Democrats in the district- 156,361, as compared to the Dem's 130,645- so winning over Independents will be extra important for Barber.

Barber, 66, has held a fundraising advantage over Kelly for most of the race. He's raised about $1.2 million in his campaign cycle, while Kelly has raised just under $700,000, according to campaign finance disclosures.

Outside money has poured into the race- more than $2.2 million has been spent by groups like the Democratic Congressional Campaign Committee, the National Republican Campaign Committee, the pro-Democratic super PAC House Majority PAC, and the pro-Republican super PAC American Crossroads, according to the FEC. A majority of that spending has been in support of Kelly (or opposing Barber.)

Experts in Arizona state politics view the race as a toss-up, but despite this, civility has ruled between the two men throughout the campaign.

"There have been two debates, one on TV, one at the Jewish Community Center, and that's it. Those debates were relatively civil," said Milward.

The reason behind the civility between the two men is, of course, likely a result of the sensitive nature of the situation, following the assassination attempt on Giffords. Gone for obvious reasons are the "Get On Target For Victory" events held in 2010 where supporters were invited to shoot an M16 with Jesse Kelly. Instead, the back and forth between the two candidates has mainly centered on entitlement issues like Social Security, and Medicare- issues that Giffords and Kelly battled over in 2010.

"I think that was the point of greatest difference in the Giffords and Kelly campaign in 2010, because Jesse Kelly had taken a number of stands on questioning the viability of Medicare and Social Security," Milward said. "So this was a point of cleavage between the two candidates in 2010, and I think this has played out in 2012 with Kelly trying to reassure seniors that he's not a, basically going to eliminate both programs."

The race has not been totally devoid of negative discourse, but Milward says that it has mostly come from the outside.

"The tenor of the outside ads that are coming in from the DCCC and the NRCC, those have been pretty nasty," said Milward.

Republicans maintain that Barber has not been forthcoming about his positions, while Democrats maintain that Republicans have attacked Barber for positions he does not hold.

"Positions on the issues matter in this race, and southern Arizonans deserve to know that Ron Barber supported ObamaCare, the Cap-and-Trade energy tax and Obama's reelection," said Daniel Scarpinato, spokesman for the NRCC. "With Barber trying to hide those facts, it's been important to make sure voters know the truth."

"This spring Republicans began to spend money attacking Ron Barber for positions he doesn't hold or votes he didn't take and it hasn't stopped since," Jesse Ferguson, spokesman for the DCCC said. "Our efforts have held Tea Party candidate Jesse Kelly accountable for his own radical ideas that he said on tape - like privatizing, phasing out and eliminating Social Security and Medicare."

Super PAC's on both sides of the aisle have received criticism for striking a negative tone as well. An ad released by the pro-Democratic House Majority PAC showing Jesse Kelly referring to Giffords as "a hero of nothing" during their 2010 campaign was criticized for a lack of context.

On the Republican side, an email sent from a conservative Super PAC featuring a picture of Jesse Kelly holding an assault rifle- the picture is also from the 2010 campaign- drew negative attention. The Super PAC- called "Move America Forward Freedom PAC"- describes its mission on its website as "first and foremost to support our troops and their missions in the war on terror," and the PAC frequently supports former military candidates.

The ultimate winner will not have very much time until he needs to begin campaigning again. The then-congressman will have to face re-election again in November. Further complicating matters is the fact that the congressional district map in Arizona has been re-drawn, and as a result, the representative for the Arizona 8th district will actually be running in Arizona's 2nd congressional district in the fall.

"They'll be running in a different constituency so whoever wins is going to have to run in another congressional district- CD 2- which has more Democrats than CD 8 does," Milward said. "Obviously the idea is, whoever wins, if you're a sitting congress person than you should have a leg up in the next election even if you're in a slightly different district."