When it comes to investing, looking for the best mid-cap stocks -- that is, shares of businesses with market capitalizations in the approximate range of $2 billion to $10 billion -- can offer an attractive balance between growth potential and relative stability. 

To that end, we asked three top Motley Fool contributors to each pick a mid-cap stock that they think investors would do well to buy right now. Read on to learn why they like Pandora Media (P)Exelixis (EXEL 1.26%), and Tanger Factory Outlet Centers (SKT 0.23%).

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IMAGE SOURCE: GETTY IMAGES.

Pandora's latest quarterly beat is just the start of this song

Steve Symington (Pandora Media): When I singled out Pandora Media as a top stock Wall Street was overlooking in early May, the music streaming company's new CEO, Roger Lynch, was still in the earliest stages of implementing a plethora of changes to reinvigorate growth. Sure enough, the stock popped more than 20% a few days later when the first fruits of those efforts began to shine through -- and as Lynch promised, they would gain momentum "over the course of 2018 and beyond."

As of this writing, however, Pandora stock is soaring once again on the heels of its even more encouraging second-quarter 2018 results. More specifically, adjusted revenue climbed 12%, far exceeding the 7% midpoint of its guidance range with the help of continued ad-hour trend improvements and a 67% increase in subscription revenue. And Pandora's adjusted net loss of $0.15 per share not only beat expectations by a penny, but also narrowed significantly from a loss of $0.21 per share in the same year-ago period.

But arguably most exciting, Lynch teased that Pandora is still in the "early innings of turning things around," suggesting the company will be able to ride new partnerships, ad-tech improvements, and expanded programmatic advertising solutions to accelerate their growth going forward.

So even with Pandora's healthy rebound from its 52-week low set earlier this year, I think the stock still offers investors today a compelling option to continue beating the market.

This biotech mid-cap stock is a screaming value

Sean Williams (Exelixis): Feel free to refer to me as a "homer," but I struggle to find a more attractive mid-cap stock that cancer-drug developer Exelixis -- a company I've owned for more than four years.

The allure of Exelixis can be traced to its lead drug, Cabometyx. Initially, it got off to a rough start, with the Comet trials for metastatic castration-resistant prostate cancer falling well short of the mark in 2014. However, Cabometyx hit the "trifecta" in second-line renal cell carcinoma (RCC) -- statistically significant improvements in overall survival, progression-free survival, and objective response rate -- and earned a label expansion to first-line RCC, ahead of cancer immunotherapy blockbuster Opdivo, which was developed by Bristol-Myers Squibb (NYSE: BMY). As a clear go-to therapy in RCC, Cabometyx should remain a cash cow for Exelixis for the foreseeable future.

Additionally, Exelixis and partner Ipsen reported in October of last year that Cabometyx met its primary endpoint in the pivotal Celestial trial for advanced hepatocellular carcinoma (HCC). This set up the duo's supplemental new drug application filing this year, and the upcoming PDUFA decision date of Jan. 14, 2019. With Cabometyx improving median overall survival to 10.2 months from eight months for the placebo, and more than doubling progression-free survival to 5.2 months from 1.9 months with the placebo, a label expansion seems very likely. 

Altogether, Exelixis is seeing solid growth in both indications of RCC, is poised to launch in HCC next year (assuming all goes well with the FDA), and could see added revenue through combination opportunities with Bristol-Myers' Opdivo in RCC, as well as with partner Roche (NASDAQOTH: RHHBY) via Cotellic, a therapy designed to treat a specific type of advanced melanoma, in combination with Zelboraf.

Sporting a compound annual growth rate of 30% through 2021, and valued at less than 19 times forward earnings, Exelixis looks to be a screaming value.

The retail apocalypse is overstated

Reuben Gregg Brewer (Tanger Factory Outlet Centers, Inc.): The retail apocalypse isn't necessarily a sign that the world will only be online, but, rather, that a new option (the internet) is changing the retail landscape. One of the best dividend options in the retail space today is Tanger Factory Outlet Centers, a real estate investment trust that owns exactly what its name implies.

Tanger allows you to sidestep picking the retailers that will survive and instead focus on owning the locations in which retailers will want to put their stores. Tanger owns 44 outlet centers and has never seen its occupancy fall below 95% in any calendar year since it came public in 1993. Sometimes, that requires granting rent concessions to retailers, but a consistently high occupancy tells you volumes about Tanger's well maintained and desirable locations.   

It's also conservatively run. The investment-grade REIT covers its interest expenses by over five times. The 5.7% yield, meanwhile, is backed by a dividend that's been increased every single year since its IPO. In 2017, the funds from operations, or FFO, payout ratio was roughly 60%, providing ample coverage for the distribution.   

Retailers, Tanger's customers, are clearly having a tough time right now and that's flowing through to the REIT's results. It is projecting that net operating income could fall around 0.5% in 2018, a tiny sum largely driven by rent concessions and tenant bankruptcies. Occupancy is expected to hover around 95%. Despite these headwinds, it expects FFO to increase as it benefits from properties recently opened or expanded. Overall, the portfolio and the company's finances remain in good shape.     

SKT Chart

SKT data by YCharts.

Worried investors, however, have punished the stock (its down nearly 30% from early 2016 highs) and pushed the yield higher than it was during the deep 2007 to 2009 recession. Unless you believe brick-and-mortar stores are dead, this solid retail REIT should have no problem adjusting along with its retailer customers and to thrive when the overhyped retail apocalypse story has finally run its course.

The bottom line

We can't absolutely guarantee that these three mid-cap stocks will go on to deliver satisfactory returns for shareholders from here. But if Pandora management is right that they're in the early stages of their turnaround, and given Exelixis' attractive valuation relative to its expected growth, as well as Tanger Factory Outlet's high dividend and solid financial position, we think chances are high that they'll do exactly that. And we think investors today wuld do well to put their money to work accordingly.