There are a couple clear signs of the Valar throwing a little nudge during the War of the Ring. I think the biggest area of help is Aragorn and the Grey Company's taking of the Black Ships. After they had taken the ships they received a goodly wind to speed them on their way (Manwe, lord of the air) and a mist surrounded them on the water (Ulmo, lord of the Sea). There were a couple more times I saw little hints at it but I can't recall them off the top of my head.
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