targeting properties with back taxes

[Umair Baig]

Hello Biggerpockets! 

I am doing a little research on targeting home owners who have properties with back taxes on them. I am planning to launch a direct mail campaign to properties that would be going to the tax sale this year, so mailing them a letter before the state takes the property and offering them cash. My question is can you wholesale these properties? Does anyone have any experience with this? is this a profitable niche?