The stock market took a pause on Tuesday, moving just slightly lower after Monday's huge gains. Investors are bracing for Tuesday night's debate between President Donald Trump and former Vice President Joe Biden, with the potential for market volatility that could result from political events as the campaign approaches its final month. Just after 11 a.m. EDT, the Dow Jones Industrial Average (^DJI 0.42%) was down 172 points to 27,412. The S&P 500 (^GSPC -0.93%) lost 14 points to 3,337, and the Nasdaq Composite (^IXIC -2.11%) gave up 17 points to 11,101.

Dealmaking has been an important aspect of the stock market's recovery since March. Not every announced deal gets completed, but fitness-device specialist Fitbit (FIT) got some good news in its efforts to join forces with Alphabet's (GOOG -1.33%) (GOOGL -1.43%) Google that spurred shareholder interest. Meanwhile, Tortoise Acquisition (SHLL) continued to gain ground on news that it cleared a key milestone in its own efforts to fulfill its purpose and merge with a privately held company.

Fireworks being launched from a central spot.

Image source: Getty Images.

Fit to be tied

Shares of Fitbit were higher by 6% on Tuesday morning. After months of uncertainty, the maker of wearable fitness products got new life in its plans to be acquired by Google.

It was nearly a year ago that Fitbit and Google decided to join forces. The roughly $2 billion acquisition created some consternation among regulators who didn't necessarily want health, fitness, and location data from Fitbit devices going into Google's arsenal of user information.

Some investors had started to fear that the deal wouldn't go through. However, Google just said that it would not only keep Fitbit data separate from the rest of the company, but also support other wearable products using the Google Android platform. It hopes those measures will be enough to get especially tough regulators in the European Union to approve the deal.

Unfortunately, there's only limited upside for Fitbit shareholders. With the merger set to take place at $7.35 per share, the current price gives only about 5% upside. That's not much reward, given the potential for a big drop if the Google deal falls through.

Hyliion to take over Tortoise

Elsewhere, shares of Tortoise Acquisition were higher by 4%. The news that its long-awaited merger with electric-truck drivetrain manufacturer Hyliion would take place came out during the day Monday, and investors remained optimistic about the move.

As a special purpose acquisition company, Tortoise's mission was to find a privately held company that wanted to come public through a reverse merger. Tortoise found Hyliion back in June, but it took several months to get through all the paperwork and other requirements. Shareholders had to approve the merger, and that's what happened Monday afternoon.

As a result, Hyliion will start trading under the ticker symbol HYLN once the merger is formally complete. Tortoise expects that to happen on Thursday, perhaps with the official change to come for trading on Friday.

Stocks related to electric vehicles have been volatile lately. Yet that isn't stopping investors from being excited about Hyliion finally getting its chance to shine in the public spotlight.