Mauer and Morneau are both four-time All-Stars, while Span has yet to be named an All-Star in his five-year career. Morneau is on the ballot as designated hitter for the first time in his career.
Fans can cast their votes for starters up to 25 times at MLB.com and all 30 club sites -- online or via your mobile device -- using the 2012 All-Star Game MLB.com Ballot until June 28 at 10:59 p.m. CT.
Fans can also once again participate in the State Farm Home Run Derby Fan Poll. Fans will have the opportunity to select three players in each league who they would most like to see participate in the State Farm Home Run 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 7 p.m. CT on July 9.
The 2012 American League and National League All-Star teams will be unveiled on 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 July 10. Come to MLB.com for 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.
Other Twins on the ballot are first baseman Chris Parmelee, second baseman Alexi Casilla, shortstop Jamey Carroll, third baseman Danny Valencia, and outfielder Ben Revere, who was optioned to Triple-A on Saturday. Ryan Doumit, who has seen time in right field and behind the plate, is not on the ballot, but he can be voted in as a write-in candidate.
Fans can also vote at Target Field starting on April 27, with in-stadium balloting concluding on June 13.
Rhett Bollinger is a reporter for MLB.com. Read his blog, Bollinger Beat, and follow him on Twitter @RhettBollinger. This story was not subject to the approval of Major League Baseball or its clubs.