NEW YORK - Shares of Trump Media & Technology Group, which is majority-owned by former U.S. President Donald Trump, sank to record lows on Tuesday, following the Republican presidential candidate's recent return to rival social media platform X.

Trump Media shares dropped to as low as $21.33, down more than 4%. The stock finished down 3.7% at $21.42, marking the eighth consecutive session of losses.

Trump's dwindling lead in polls and election betting markets in recent weeks has also hit the stock, which has been seen by some retail traders as a bet on whether Trump would win a second term.

"I've always looked at Truth Social and DJT as a voting mechanism versus an investment mechanism," said Lou Basenese, president and chief market strategist at MDB Capital in New York. "The valuation never made sense in relation to the fundamentals."

The stock had reached an all-time high of $79.38 during their Nasdaq debut on March 26 following a merger with blank-check company Digital World Acquisition Corp.

Earlier this month, Trump Media - whose main asset is the Truth Social app - reported a quarterly loss of $16.4 million and revenue of just $837,000. The company has a market value of about $4.3 billion, down from over $8 billion earlier this year.

Trump is expected to be eligible to begin cashing out his nearly 60% stake - or 114.75 million shares - in his social media company when the insider lockup period expires next month.

"It's always traded in line with his odds of winning or losing, and that's what we're seeing now that the race is tight and the probability of him winning has narrowed. And I think it's hitting record lows also because you're coming up against the insider lockup," Basenese added.

Trump began posting on the X platform last week for the first time in nearly a year, coinciding with an interview with owner Elon Musk.

Trump in recent weeks has lost his sizeable lead in polls against Vice President Kamala Harris, the Democratic candidate.

With 78 days to go before the Nov. 5 vote, contracts for a Harris victory are trading at 56 cents, with a potential $1 payout, on the PredictIt politics betting platform.

Trump contracts are at 46 cents, down from as much as 69 cents in mid-July.

(Reporting by Chibuike Oguh in New York; Editing by Daniel Wallis)