Ok, this one is much easier. The American League had a number of candidates from a variety of competitive teams. The National League has far fewer competitive teams, which limits the number of qualified candidates.
Basically it boils down to Albert Pujols vs. Ryan Howard (with a nod to Carlos Beltran).
First we'll start with Beltran. He had a "paltry" OPS. of .982. But like Jeter, his numbers go up as the situation becomes more important. An OPS. of 1.159 with runners in scoring position and a 1.180 OPS. with runners in scoring position and two outs is not too shabby. Moreover, he has 38 Win Shares, 1 beyond Pujols, who leads baseball. His VORP of 67.6 is mediocre compared to Pujols and Howard, however.
But we must remember that he plays a gold glove center field and stole 18 bases. And given Rule 1, I might be willing to put him ahead of Howard, but Pujols is too much better.
Howard's big advantage is his games played. Howard played in 159, compared to Pujols' 143 and Beltran's 140. He also has a high 1.084 OPS. and an OBP. of .425, far better than Beltran. But like David Ortiz and Frank Thomas, his numbers are deceiving. He hits far better with no one on than with runners in scoring position (he batted .256 with runners in scoring position and .247 with runners in scoring position and two outs). His OPS. in both circumstances is below .950.
He also doesn't play much defense and he only had 31 Win Shares.
Let's look at Pujols. An OPS. of 1.102 only increases with runners in scoring position (1.337) and with runners in scoring position and two outs (1.407). He had a mindboggling .581 OBP. (and a .435 average) and a .826 SLG. His OPS. is just a tad shy of 1.300 with runners on and two outs.
He had 39 win shares, a 86.6 VORP (5 runs better than Howard) and practically carried his mediocre team to the postseason.
If I had to rank them I'd probably go with Pujols, Beltran, and Howard. Howard vs. Beltran is tough because of Howard's extra games, superior OPS., and substantially better VORP. Beltran plays (much) better defense, hits better in big situations, and has 7 more win shares.
Pujols, however, has the best OPS, batting average, OBP., SLG., OPS., OPS. with runners on and two outs, with runners in scoring position, and in scoring and two outs. He also has the most Win Shares and the highest VORP. And he singlehandedly led his team to the playoffs.
I can't see Pujols not winning this award. It's not even close.