The nonprofit Cambridge Main Street announced this week that it will help two entrepreneurs set up new shops this holiday season through its Pop-Up Project, a competition in which contestants who submit the best business concepts win rent-free storefronts to test out their retail business ideas in November and December.

"These are exciting times in downtown Cambridge," said Jim Duffy, Main Street's executive director. "These new businesses-a jewelry store and a pet boutique-will add excitement and vibrancy in the months ahead, building on the buzz around the Shore about our downtown since the recent openings of the expanded Jimmie & Sook's restaurant and the brand new High Spot restaurant."

This is Main Street's second annual Pop-Up Project-the first won a statewide award and national attention in economic development trade publications. One of last year's two winners, Malina Custom Leather, signed a lease after the contest and remains in business today. The project was conceived by Main Street's board president, Phil Feldman of RPS ISG Insurance.

The jewelry store Bliss will be moving into 501 Poplar Street, while the pet boutique Pet Threadz will be moving into 315 Gay Street. Both locations are in the same building at the corner of Gay and Poplar streets, and both businesses are shooting to open on Friday, October 28.

Bliss owner April Dean Whitacre brings 16 years of retail experience to her newest project, including operating an existing Bliss store in St. Michaels. That store will remain open as Whitacre expands to this second location.

Most of the jewelry and accessories in Bliss will be priced below $30, and Whitacre believes that affordable price point will help fuel her success. Another reason she is confident that the Cambridge Bliss will succeed is that it's "among good company. I have always regarded the shopping in Cambridge to be of high quality, and I'll be honored to join the established retail community downtown."

Whitacre previously owned and operated two other stores, the award-winning Mind's Eye Craft Collection and the Charisma Clothing Boutique. She has been an executive with the St. Michael's Business Association and helped launch that community's successful annual Midnight Madness, a highlight of the Christmas shopping season.

"We welcome April and her staff to our downtown community and really look forward to making the most of her input and experience as we all work together to make downtown Cambridge a destination for customers that's even more fun and engaging than it is today," Duffy said.

Pet Threadz will healthy foods, unique treats, custom-made clothes, bowls, toys, and more. Operated by Amanda and Virginia Knauff, the shop will deliver a boutique atmosphere. The business is an outgrowth of an online-only business called Lillie O. Couture; this will be the Knauff's first retail location.

Both businesses expect to be fully stocked in time for the monthly Second Saturday festivities on Nov. 12. That event will focus on these openings and one other that's happening independently of the contest-a new Recreation Center offering kids activities, family-friendly snacks and meals, and more at 504 Poplar Street.

"One thing that's really great is that both of these winners are looking not just to operate for the two-month duration of the contest prize, but to continue in our downtown going forward into 2012," said Main Street's Duffy. "We welcome these entrepreneurs to our town, and our Main Street volunteers will be doing everything they can to support their efforts."