Voters in Georgia’s 3rd District head to the polls Tuesday to determine the Republican nominee for the congressional seat long held by Lynn Westmoreland.

The runoff race has grown to be a hotly contested one in recent weeks, with Washington-based groups pouring hundreds of thousands of dollars into the western Georgia district in what has become a proxy fight for control of the GOP.

Here’s what you need to know:

Where is the 3rd Congressional District?

The west-central district includes portions of 13 counties: Carroll, Coweta, Fayette, Harris, Heard, Henry, Lamar, Meriwether, Muscogee, Pike, Spalding, Troup and Upson.

Who are the candidates?

State Sen. Mike Crane and dentist and former West Point Mayor Drew Ferguson emerged from a crowded seven-man primary in May with virtually the same number of votes. Turnout is expected to be low but will hold the key to determining the winner.

Crane and Ferguson represent drastically different styles, temperaments and strands of Republicanism.

The former is an evangelical, socially conservative firebrand not dissimilar from U.S. Sen. Ted Cruz, whom he brought to his hometown of Newnan for a campaign event Friday. Crane built a statewide profile over the past year by leading the opposition to Gov. Nathan Deal’s veto of so-called “religious liberty” legislation. The campaign arm of the conservative Club for Growth has been cutting ads on his behalf, and he recently received an endorsement from Gun Owners of America.

Ferguson, meanwhile, is an affable ex-small-town mayor who’s focused his campaign on his efforts to economically rebuild his hometown after Kia Motors opened a plant nearby. He’s consolidated the support of the business community and so-called GOP “establishment,” racking up endorsements from Westmoreland, U.S. Sen. Johnny Isakson and all five of the other candidates who ran in the primary. The national and state branches of the Chamber of Commerce have committed hundreds of thousands of dollars to securing a win for Ferguson.

What’s the biggest issue in this race?

The race may be influenced by national groups duking it out for the soul of the Republican Party, but the most potent issue locally has been law enforcement. The hubbub has centered on remarks Crane made about no-knock warrants at a GOP gathering this spring.

“You come to my house, kick down my door — if I have an opportunity, I will shoot you dead,” Crane said. “And every one of you should do the same. It is the only area where the law enforcement community and I differ, but they have to understand the law.”

Attack ads from groups allied with Ferguson have framed Crane as anti-cop during a time of national unrest following several recent shootings involving the police. The state senator has shot back with spots of his own underscoring his support and family ties to law enforcement.

What’s ahead for the victor?

The winner of Tuesday’s runoff will face Grantville Democrat Angela Pendley in November but will be heavily favored to win the seat due to the deep-red makeup of the district, which voted for Mitt Romney by a margin of 2-to-1 in 2012.

A volunteer with a background in health care, Pendley has vocally defended the Affordable Care Act but acknowledges that President Barack Obama’s signature legislative accomplishment also has its share of problems. She said the country has enough gun laws already in place and that current statutes should be enforced.

Where can I find voting information?

By visiting the Georgia Secretary of State Office's website at sos.ga.gov/index.php/elections .