The S&P 500 index has gained momentum with a rally of 14% for the year. However, the rally is largely concentrated to blue-chip stocks. There are dozens of attractively valued growth and penny stocks to buy. Among small-cap stocks for high returns, I believe certain names are worth buying at current levels for multi-bagger returns.

Aggressive revenue growth, quality assets, strong order backlog, and a healthy balance sheet are the key reasons supporting the buy thesis. On a conservative basis, the small-cap stocks discussed can triple in the next 24 months.

In terms of the broader market outlook, the fed’s dovish stance is positive. The dollar is likely to weaken and risky asset classes are poised to rally.

It’s therefore a good time to remain invested and consider exposure to growth stocks. Of course, I would however remain overweight on blue-chip dividend stocks.

Let’s discuss the triple returns small-cap stocks to buy.

Marathon Digital (MARA)

Marathon Digital (NASDAQ:MARA) stock has skyrocketed by 240% for the year. The rally has been from deeply oversold levels and I remain bullish on MARA stock. Bitcoin (BTC-USD) seems to have regained momentum and currently trades over $28,000. With halving due in 2024 for the cryptocurrency, the outlook is bullish.

Specific to Marathon Digital, the company has been on an aggressive expansion spree. As of May, the company had increased its operational hash rate to 15.2EH/s. Further, the guidance is to boost capacity to 23EH/s by the end of this month.

This will translate into vigorous growth in Bitcoin mined per month. With the crypto trending higher, the outlook for EBITDA margin expansion and cash flow upside is robust.

It’s also worth noting that as of May, Marathon had $97.3 million in cash and $33.7 million in digital assets. Financial flexibility is high for pursuing aggressive growth beyond the current expansion plan.

Piedmont Lithium (PLL)

Piedmont Lithium (NASDAQ:PLL) is another small-cap stock with an upside of 40% for the year.

I expect the positive momentum to sustain for this lithium play. In my view, over a period of 24 months, PLL can deliver 3x returns.

As an overview, the company has 100% ownership in the Tennessee and Carolina lithium assets. Both these assets have a combined net present value of $5 billion. Additionally, the company has 35% and 50% economic interest in the Quebec and Ghana project respectively.

Given the asset base, Piedmont seems massively undervalued at a current valuation of $1.2 billion. With the Quebec project likely to deliver first production in 2023, there is a stock upside catalyst.

Lithium prices have corrected from highs in 2023. However, considering the supply gap in the coming years, the correction is unlikely to sustain. Once lithium trends higher, PLL stock will have an additional upside catalyst.

Borr Drilling (BORR)

At a forward price-earnings ratio of 13.5, Borr Drilling (NYSE:BORR) stock is another small-cap stock for high returns. The stock has trended higher by 40% for the year and the positive momentum is likely to sustain on the back of robust financial performance.

As an overview, Borr Drilling is a provider of modern jack-up fleet. The company has global presence with 22 contracted rigs and two under construction. With a contract backlog of $1.64 billion, Borr Drilling has clear revenue and cash flow visibility.

For the year, Borr has guided for 71% growth in revenue to $760 million. EBITDA growth is likely at 141% to $380 million. Healthy EBITDA margin expansion is on the back of new orders at a higher day rate. With the possibility of strong cash flows, the company’s credit metrics will improve.

I also believe that the worst part of the correction for oil is done. As crude trends higher, order intake is likely to remain strong.

On the date of publication, Faisal Humayun did not hold (either directly or indirectly) any positions in the securities mentioned in this article. The opinions expressed in this article are those of the writer, subject to the InvestorPlace.com Publishing Guidelines.