Sometimes an All-Star choice is obvious. Take first base in the National League, where Joey Votto is the best player this year and has been great for a long time. Obviously fans are free to vote for whomever they like, but it would be hard for an unbiased observer to argue that someone deserves the vote over the Reds' one-time NL MVP Award winner.
Sometimes it's quite a bit more difficult. As All-Star voting continues to ramp up, with fewer than six weeks left until the 2012 Midsummer Classic, here is a look at a few cases where the choices might not be immediately evident.
NL catcher: Do you want the best story, the best season or the best player?
A.J. Ellis of the Dodgers has been a revelation and an on-base machine. The Phillies' Carlos Ruiz is putting up the best overall offensive numbers. St. Louis' Yadier Molina has been the league's best all-around player at the position since the start of last season.
So let's look closer. Ruiz has the highest batting average, highest slugging percentage, highest OPS and is tied with Molina in homers and RBIs. Ellis leads them all in on-base percentage, but he has played fewer games, has fewer at-bats and plate appearances and has hit for less power.
Ruiz wins when it comes to WAR (wins above replacement, a way to measure a player's total contributions), scoring 2.5 according to Fangraphs.com and 2.4 according to Baseball-Reference.com. Ellis' fWAR (WAR according to Fangraphs) is tied with Ruiz, while he trails at 2.0 at Baseball-Reference. Molina ranks behind them both in both systems. Meanwhile, Molina is the incumbent and the recognized leader defensively. It's hard to go wrong.
American League outfield: By pretty much any reasonable definition, Josh Hamilton makes the cut, whether you're looking at this year or the long view. The other two spots are a bit more challenging, though.
Curtis Granderson is having another excellent year at the plate, and in light of his 2011 season, he'd seem to be a safe call, but by virtually every advanced statistical measure, his defense rates poorly. Jose Bautista is having a down year, though he's come back to life recently.
All of which would seem to open the door to some new contenders. The Tigers' Austin Jackson ranks second to Hamilton among AL outfielders in OPS, and third behind Hamilton and Adam Jones in fWAR. Speaking of Jones, his power breakout makes him an intriguing candidate as well. He's fourth in OPS thanks in large part to his 14 home runs, and he's second in fWAR.
AL shortstop: The question here is a bit like the one at catcher in the NL: Do you want the bat, the star or the all-around stud?
The best bat at the position belongs, fairly easily, to Cleveland's Asdrubal Cabrera. He leads the position in on-base, slugging and doubles, and he's third in RBIs. But he's not exactly the best defender, with various systems rating him somewhere between so-so and not good. The leader in fWAR, for his combination of bat and glove, is Texas' Elvis Andrus, and it's easy to envision the 23-year-old holding down that spot for a while (unless Rangers prospect Jurickson Profar forces him to another position).
And then there's the old lion, Derek Jeter. His early-season sizzle has fizzled a bit, but he's still been the league's second-best-hitting shortstop. His defense continues to rate poorly by statistical measures, but well, he's Derek Jeter. The game does have the word "Star" in its name, after all.
NL second base: And once more, it's a what-you-value question. Omar Infante, Jose Altuve and Dan Uggla all have cases, and it's a matter of what you want in an All-Star.
Uggla has the longest track record, the highest on-base percentage, and believe it or not, some of the better keystone defense this year, according to some metrics. He ranks average to slightly above with the glove, according to the Plus-Minus system, UZR and Total Zone fielding runs. He's hit for less power and a lower average than his Miami replacement, but overall, he's having an excellent year.
That replacement, Infante, has had the best bat. He's hitting for average and power, but his defense ranks quite poorly, so the various flavors of WAR don't rate him too highly. And then there's young Altuve, who combines bat, glove and charisma as one of the game's more entertaining young players.
Fans can cast their votes for starters up to 25 times at MLB.com and all 30 club sites -- online or via a mobile device -- using the All-Star Game MLB.com Ballot until June 28 at 11:59 p.m. ET.
Fans can also once again participate in the State Farm Home Run Derby Fan Poll. Fans have the opportunity to select three players in each league who they would most like to see participate in the Derby. The 2012 State Farm Home Run Derby -- part of Gatorade All-Star Workout Day -- will be broadcast live on ESPN, ESPN HD, ESPN Deportes and ESPN Radio in the United States beginning at 8 p.m. ET on Monday, July 9.
The American League and National League All-Star teams will be unveiled on Sunday, July 1, on the 2012 MLB All-Star Game Selection Show, televised nationally on TBS. Baseball fans around the world will then be able to select the final player on each team via the 2012 All-Star Game Final Vote on MLB.com.
And the voting doesn't end there. The final phase of All-Star Game voting will again have fans participating in the official voting for the Ted Williams All-Star Game Most Valuable Player Award presented by Chevrolet. During the Midsummer Classic, fans will vote exclusively online at MLB.com via the 2012 All-Star Game MLB.com MVP Vote, and their voice will represent 20 percent of the official vote determining the recipient of the Arch Ward Trophy.
The 2012 All-Star Game will be played at Kauffman Stadium on Tuesday, July 10. MLB.com will have extensive online coverage of the All-Star Week festivities.
The 83rd All-Star Game will be televised nationally by FOX Sports, in Canada by Rogers Sportsnet and RDS, and worldwide by partners in more than 200 countries via MLB International's independent feed. ESPN Radio and ESPN Radio Deportes will provide national radio coverage of the All-Star Game. MLB Network and Sirius XM also will also provide comprehensive All-Star Week coverage. For more information, please visit allstargame.com or royals.com/asg.
Matthew Leach is a writer for MLB.com. Read his blog, Obviously, You're Not a Golfer and follow him on Twitter at @MatthewHLeach. This story was not subject to the approval of Major League Baseball or its clubs.