Stalemate? How about Hannibal wins?
Stalemate isn't the best Hannibal could have achieved. The Alps crossing wasn't so stupid-what hurt Hannibal with the crossing are these things: 1) His 'allied' guides abandoned him. 2) An early winter. 3) Attacks by mountain tribes. Supposing that winter didn't come early is enough to give Hannibal a larger force going into Italy. Instead of 26,000 men, Hannibal has more like 34,000, and quality men at that.
Another crucial point in his campaign is the attempt on Cumae and Nola. Hannibal had already demonstrated his complete superiority in the field; now he had to show Rome's allies that Rome couldn't necessarily protect them even behind their walls.
At Cumae his seige tower was burnt. With no allies in town offering to betray it to him, he moved on eventually to Nola. Some Nolans had approached him offering to betray the town, but when Hannibal showed up nothing happened. In 215 Hannibal went back to make preparations for an assault.
Here's where things really started to fall apart. Mago was to be sent to Italy with 12,000 infantry and 1,500 cavalry, but was sent instead to Spain. Carthage had just sent an army to Spain under Himilco, but upon hearing of Hasdrubal's defeat the Senate sent Mago there. So in addition to losing Mago, a senior commander, Hannibal was denied reinforcements at a crucial time. If Mago is sent to Italy as planned, he joins up with Hanno and his 17,000 Bruttians. Therefore there is no Battle of Calor River-the Roman army would have hidden in Beneventum rather than take on such a large force.
With this army Hannibal assaults Nola and takes the town. Marcellas either escapes with a small number of men or is killed in the fighting. Either way, Hannibal has now secured Capua's southern flank, made it easier for him to move troops back and forth between Bruttium and Campaignia, and encouraged towns that were sitting on the fence to throw in their lot with him.
From this point much could still happen, however, with the capture of Nola (which contained many who were friendly to him) Hannibal keeps the initiative and creates a difficult scenario for the Roman consuls to continue protecting the remaining Campaignian towns, including the port of Cumae.