Chicago - The stars are aligning for a robust year in retail, but the spoils aren't likely to be shared equally.

Decreasing unemployment, brightening consumer confidence and plummeting gas prices point to a boost in consumer spending in 2015 that should be more widespread and democratic than the spotty economic recovery of the past few years, experts say.

Retail sales are expected to rise 4.5 percent this year, a full percentage point more than the 3.4 percent growth in 2014, according to Kantar Retail, which excluded car dealers, gas and food service from its analysis.

Retail sales total $2.6 trillion annually and constitute a substantial portion of consumer spending, which accounts for 70 percent of the nation's GDP.

After several years of spending gains driven by the wealthy, the consumer economy "is in transition" as more lower- and middle-income households start to see financial improvements, said Ellen Zentner, senior U.S. economist with Morgan Stanley.

In 2013, the fastest growing category in consumer spending was personal aircraft, followed by pleasure boats, she said. Today, computers and TVs are back on top.

"That's important because that's normal," Zentner said.

Still, "growth continues to be uneven and the particular retailers that will benefit are increasingly fragmented," said Frank Badillo, chief economist at Kantar.

Not only has the gulf between rich and poor widened as hourly wages remain stagnant, but there have been fundamental changes in where and how people like to shop.

Online sales, though still 10 percent of total retail sales, are expected to grow 15 percent this year, same as in 2014, while sales at physical stores are expected to rise 3.6 percent, according to Kantar.

Much of the growth in retail, Badillo said, will be driven by people under age 34, both on the lower- and higher-end of the income scale, as that age group has seen the greatest employment gains.

As a result, smaller stores, from neighborhood convenience stores to upscale specialty stores, will be a key growth category because they appeal to younger people who tend to live in urban environments, dine out and shop on an as-needed basis, Badillo said.

Here's how various retail sectors are expected to fare.

Dollar stores

Dollar stores, which performed well during the recession and have became one of the fastest growing retail formats, are poised for a promising 2015. That's thanks largely to falling gas prices, as their lower-income customers tend to be affected most by having a few more dollars in their pockets, said Ken Perkins, an analyst at Morningstar.

Because the typical dollar-store transaction is modest, an average of $10 or $11, the addition of a single item generates a healthy sales lift, Perkins said.

But it may take time for people to feel as if they have extra cash.

And gas prices aren't always a reliable predictor of how people will spend, Zentner said. More important is wage growth, which Zentner said he expects to accelerate slightly to 2.5 percent in 2015, from 2 percent last year.

Dollar stores face other challenges. Cuts to food stamp benefits and food inflation have put pressure on the wallets of their core customers, Perkins said. And they face increased competition from Wal-Mart and other large discounters experimenting with smaller-store formats to attract young shoppers.

Still, dollar store chains continue to open new stores at a brisk pace. Dollar General, the nation's largest dollar chain, plans to open 730 new stores this year, up from 700 opened in fiscal 2014. Dollar Tree, the second largest chain, opened 300 stores during the 39 weeks ended Nov. 1.

Both chains are vying to buy smaller rival Family Dollar, which would bring savings through increased buying power and supply chain consolidation, Perkins said.

Luxury

Aside from sinking with the stock market during the depths of the economic crisis, the U.S. luxury market has been on stable footing for years, said Oliver Chen, a luxury analyst at Cowen and Co. With the S&P 500 index strong and housing valuations stabilizing, the climate is ripe for wealthy people to continue buying fancy things.

"Wealthy people have always had money to spend," Chen said. "It's just about confidence."

Sales of personal luxury goods in the U.S. grew 5 percent in 2014 in constant exchange rates, fueled by a steady pace of store openings in second-tier cities and growing tourism, according to a report by Bain and Co. The Americas have become a key growth driver of global luxury sales as the broader luxury market slows because of events in Asia, Europe and Russia, the report said.

But new customers aren't buying luxury in the traditional way. Off-price stores are gaining traction among value-seeking shoppers, and they have nearly doubled their market penetration in three years. The second-hand luxury market is booming. And high-end brands that aren't quite luxury are stealing some market share.

To remain relevant going forward, many luxury brands are focusing on how to attract millennials, who tend to be less impressed with a brand name than with its back story. Investing in technology to connect with its future shoppers, as Burberry was among the first to do, has been a steady trend.

Mass merchants

Modest 1.6 percent sales growth last year at general merchandise retailers, which include Wal-Mart and Target, should accelerate in 2015 "as people who have been struggling to get by begin to struggle less," said Michael Moriarty, a senior partner at A.T. Kearney.

A lot rides on the small urban formats that they've been rolling out, such as TargetExpress and Wal-Mart Express, as small-basket trips are becoming more popular, he said.

These neighborhood stores also put more emphasis on and sell more fresh food than the retailer's traditional big boxes, said Craig Johnson, of Customer Growth Partners.

"They can't build them fast enough," Johnson said. "It's like turning around a fleet."

Target, meanwhile, which also has a new CEO, is expected to regain its footing after a massive data breach in late 2013 and straying from a focus on stylish apparel and home goods.

"Target should get back to its core DNA this year," Johnson said.

Costco is expected to continue to do well in all markets.

Department stores

Department stores, where sales declined 2.1 percent in 2014, continue efforts to reinvent themselves to attract young shoppers, Moriarty said.

Despite positive holiday same-store sales increases at Macy's Inc. (up 2.7 percent) and J.C. Penney (up 3.7 percent), both retailers announced plans to close stores this year and eliminate some positions.

Macy's Inc., which includes Bloomingdale's, said it was restructuring its merchandising and marketing functions so one unified operation would support in-store and online buying.

"It became clear that we needed to get one single view of the inventory," R.B. Harrison, Macy's chief omnichannel officer, said at a National Retail Federation conference recently. "We think that positioning will help us move faster."

Macy's, which is widely lauded for its strategies that leverage its digital and physical store capabilities, such as same-day delivery, is investing heavily in mobile technology, which has become the priority of its development, he said.

"We believe we have the opportunity to become the seventh-largest online retailer, passing Netflix," Harrison said.

Nordstrom's acquisition of Trunk Club, a Chicago-based e-commerce startup that ships boxes of outfits for men to try on at home, may portend similar moves by retailers this year to seek similar ways to reach younger consumers.

"The future of this business is my knowing you and what's in your closet when you walk in the store," said Ken Morris, principal at Boston Retail Partners.