James' backup team this year? The San Francisco 49ers. Actually, based on the tweet below, it seems like James' backup team is whichever team Donte Whitner is playing for and Whitner happens to be playing for the 49ers.
Congrats to my homie @DonteWhitner on the game clinching INT and W! Since my Cowboys out I want him to win it all!— LeBron James (@KingJames) January 12, 2014
It's not clear how long Whitner and LeBron have been friends, but they're both from Northern Ohio and LeBron seems to regularly support Whitner on Twitter. James sent Whitner a good luck tweet before the last two NFC Championship games.
Here's LeBron's tweet from two years ago when the 49ers played the Giants:
Good luck to the homies @DonteWhitner & Ted Gin in the NFC Championship today!— LeBron James (@KingJames) January 22, 2012
And here's LeBron's tweet from last year when the 49ers played the Falcons:
Good luck to my homie @DonteWhitner! Lets get it! Remember what we talked about the other day— LeBron James (@KingJames) January 20, 2013
If the 49er makes the Super Bowl, LeBron might be able to fit the game into his schedule. The Miami Heat play in New York the night before Super Bowl XLVIII is played at MetLife Stadium in New Jersey.