They hope to make big 'gains' in Congress in the coming election. [=they hope that many more members of their party will be elected to Congress]
Her hard work 'gained' her their respect. [=she has gained their respect through hard work; they respect her now because of her hard work]
a stock that was one of the year's biggest 'gainers' [=one of the stocks that increased the most in value]
(..) l haven't seen you in forever. lt's only been a year. Did you do something different to your hair? -No. -You gain weight? -No. -l know! You just had a birthday. -Yeah. -Totally. Total fire sign. l knew it. -l totally knew it. (..)2004 White Chicks