The stock market continued to move steadily higher on Tuesday, sending most major benchmarks to fresh records. A day after lawmakers in Washington settled on a deal to reopen the federal government for three more weeks, investors turned their attention back to the earnings front, and a positive report from the leading provider of streaming video services helped to spur yet another upsurge on Wall Street. Several other stocks had substantial gains, some attributable to definite news, while others climbed purely on speculation. Mattel (MAT -0.66%), Inovio Pharmaceuticals (INO -5.10%), and Logitech International (LOGI -0.99%) were among the best performers on the day. Below, we'll look more closely at these stocks to tell you why they did so well.

Mattel climbs as merger speculation once again swirls

Shares of Mattel picked up 10%, with most of the gains coming in the mid-afternoon. Rumors once again circulated that the long-ailing toymaker might pursue merger discussions with industry rival Hasbro (HAS 0.60%), whose shares also gained ground on the day, but neither company confirmed that speculation. It isn't the first time that Mattel has climbed on merger rumors, with last November's upswing turning out to be a false alarm. There's nothing to indicate that things are any different this time, but some investors clearly have reason to believe that the companies could be giving it another go to start out 2018.

Thomas & Friends Twist-N-Turn Stunt Set box wtih Fisher-Price label.

Image source: Mattel.

Inovio reports good data

Inovio Pharmaceuticals stock soared 22% after the company published promising data yesterday on its progress toward development of a universal flu vaccine. The company said that the synthetic vaccine methodology led to favorable responses in generating protective antibodies against major variations of the influenza virus, including the infamous Spanish flu from a century ago. Inovio is hopeful because of this initial success that it will be able to come up with a treatment to fight far more strains of influenza than the current seasonal vaccines that are available. As Inovio looks to expand partnerships and extend its influence, investors believe that the company has a lot of potential for growth.

Logitech has a strong quarter

Finally, shares of Logitech International gained 11%. The maker of computer peripherals and other equipment said that sales jumped by more than 20% to a new all-time record, riding strength in products related to video gaming, mobile speakers, and video collaboration. Logitech also boosted its full-year fiscal 2018 outlook for sales growth to a range of 12% to 14%, up 2 percentage points from its previous projections, and raised adjusted operating income projections by $10 million to a range of $270 million to $280 million. With this positive news, investors believe that Logitech might be in position to reverse recent share-price weakness and reward them for their patience with the company.