The biggest question mark of the 2012 NFL Draft is who do the Minnesota Vikings select with the third pick.

The Indianapolis Colts and Washington Redskins are both locked in on their choice - Andrew Luck and Robert Griffin III, respectively - which is why all eyes are on what the Vikings do at No. 3.

The conventional wisdom long suggested that the Vikings would select USC offensive tackle Matt Kalil to protect Christian Ponder, the team's No. 1 pick in the 2011 draft, but the organization has done its best to create as much mystery as possible ahead of Thursday night.

There has been scuttlebutt that Kalil could be dropping in the draft, though that could just be the Vikings trying to get someone to trade up to the third pick. The Big Lead has speculated that the Vikings would love to trade down and still grab Kalil, but doesn't have a trading partner to make the move.

In addition to Kalil, the Vikings have also been associated with LSU defensive back Morris Claiborne and Oklahoma State wide receiver Justin Blackmon. While Kalil is still the likely pick for the Vikings, here is some background information on their three possible selections on Thursday night.

Matt Kalil, offensive tackle, USC

He's easily the best left tackle in the NFL Draft and could be vital in protecting Ponder, the Vikings' quarterback of the future. He's as impressive as it gets for young lineman and could anchor the left side of the offensive line for years to come. The Sporting News, Sports Illustrated, and CBS Sports all have the Vikings taking Kalil. This is the most likely current option for the Vikings.

Morris Claiborne, defensive back, LSU

The talented corner back from LSU would be a great addition to the Vikings' weak secondary, but it could be an unlikely pick. Claiborne, who was recently ridiculed for a poor score on the Wonderlic test, could be a great help when the Vikings have to face the likes of Aaron Rodgers and Matt Stafford twice a year, as Sports Illustrated's Peter King noted in his most recent mock draft.

Justin Blackmon, wide receiver, Oklahoma State

While doubtful that the Vikings use their pick on a wide receiver, there has been some discussion about selection Blackmon. The Vikings have a lot of holes, but adding a dynamic wide receiver to the oft-injured Percy Harvin is a priority. Blackmon is probably the least likely of the three players to be drafted by the Vikings on Thursday.