rally

Fig. to unite or assemble in support of someone or something. All the other workers rallied around Fred in his fight with management. They rallied around the principle that Fred stood for.

to unite in support of someone or something. The students rallied to Betty, their elected president. We all rallied to the cause.

Invigorate someone or cheer someone up, as in This drink will pep you up, or The good news about his recovery pepped us up. [1920s] Both the verb pep and the noun pep, denoting vigor and energy since about 1910, are abbreviations for pepper, a spice with a pungent, biting quality. They also have given rise to pep rally, a meeting to inspire enthusiasm [c. 1940], and pep talk, a speech meant to instill enthusiasm or bolster morale [1920s].

Join in a common effort, as in When Mom broke her leg the entire family rallied around to help. This idiom gained currency with George F. Root's famous Civil War song, "The Battle Cry of Freedom," which urges troops to rally round the flag that goes with them into battle. [Early 1800s]