The percentage of companies with at least 10 percent of their total revenue from e-commerce grew 14 percent in 2014 from 2013, according to the fourth annual 2015 State of E-Commerce in Distribution survey, conducted by MDM and Real Results Marketing.

The improvement marks a key shift for the e-commerce channel in distribution, which continues to mature as companies recognize an increased need for a robust digital sales platform, say Jonathan Bein and Dean Mueller in 2015 State of E-Commerce in Distribution.

Two trends are shaping e-commerce, according to Bein and Mueller: It is easier and less expensive to launch an online initiative, but many distributors experience more time in the nascent stage of e-commerce maturity, typically for three to five years.

"Distributors often underestimate how long it will take to work out the operational processes for e-commerce, including inventory management, fulfillment, product content management and even Web technical support," Bein and Mueller write. "Companies that stall after working out the operational issues usually do so because their e-marketing capabilities mature slowly."

However, the growth in e-commerce wasn't as strong as respondents projected in last year's survey. Also, the percentage of respondents with 5 to 10 percent of total revenue from e-commerce remained at 20 percent, and companies with nascent e-commerce initiatives (revenue less than 5 percent) declined slightly.

Distributors said their top priorities for e-commerce are to increase new customers and orders from the website; promote the company brand; and improve ease of use.

Read more about distributors' e-commerce expectations and priorities for the year, including analysis of the five categories of e-commerce platforms, in 2015 State of E-Commerce in Distribution.