Romney’s Sunday visit to Georgia an indication that every vote could actually matter on Tuesday

Barring a dramatic upset, Newt Gingrich will win the Georgia Republican primary on Tuesday.

But Romney will be in Snellville on Sunday, obviously trying to shore up his support in suburban Atlanta, where he could end up doing pretty well and take full advantage of the state’s odd delegate allocation system.

Georgia Republicans — plus any Democrats and Independents who choose to vote on Republican ballots in the open primary — will choose 76 delegates on Tuesday.

As I understand the complex process, 3 delegates will be selected in each of the state’s 14 Congressional districts. If a candidate gets more than 50% in a district, then he’ll get all 3 of the district’s delegates. Less than 50% of the vote, and he’ll get 2 delegates and the second place vote-getter will get 1.

Those Congressional district allocations account for 42 of the 76 delegates.

The other 34 delegates will be awarded based on the proportion of the statewide vote, but only candidates who break 20% will qualify.

Gingrich seems likely to break 40% statewide, based on all the recent polling (FiveThirtyEight projects him to get about 44%), but he’ll need to break 50% in individual districts to get all 3 of that district’s delegates. It seems likely that Santorum could prevent Gingrich from getting 50% in more conservative Congressional districts, and it’s possible that Romney could win a couple of suburban Atlanta districts — and maybe even approach 50% in a couple of districts (unlikely, definitely, but don’t be too surprised given the fluidity of the race).

So Romney’s visit Sunday and any other late effort in the state will have two goals: to make sure he hits 20% in the state as a whole and to try to come in 1st or 2nd in as many districts as possible. A further goal would be to prevent Gingrich from getting 50% in any of the districts that he wins.

If Romney’s final push puts Santorum below 20%, then that will have a particularly significant impact on the latter’s delegate allocation in the state.

So Romney’s last-minute efforts are a little more complicated than simply the attempt to cement second place, as the effort has been characterized by the Political Insider at the AJC.

At the end of the day, Gingrich could end up with 40 or more of Georgia’s 76 delegates, but that home state win won’t be nearly enough to convince voters around the country that he’s a viable candidate going forward. More importantly, it won’t be enough to make any serious dent in Romney’s delegate edge (as I write this, Gingrich trails Romney by more than 150 delegates).