Yes, a humidifier can make your house feel warmer, even though it doesn’t actually raise the air temperature, because increased humidity slows down the evaporation of sweat from your skin, making you perceive the temperature as higher; essentially, you feel warmer due to the moisture in the air, not because the room is physically warmer.
Key points about humidifiers and temperature perception:
When the air is humid, sweat evaporates more slowly from your skin, causing you to feel warmer.
Your body uses sweat evaporation to cool itself, so less evaporation in humid air means you feel warmer.