Any concerns that Celine Dion couldn’t be replaced as a marquee Las Vegas attraction have disappeared.

Cher and her Caesars Palace stablemate Bette Midler have instantly joined the list of hottest attractions in Sin City, selling out the Colosseum at Caesars Palace for every concert since the departure of Dion.

Midler opened at the Colosseum in February and Cher on May 6. Midler’s initial run was 19 dates; Cher has played 16 concerts in the 4,296-seat venue. The two shows have already grossed about $24 million in ticket sales.

Promoter AEG Live does not release specific grosses, but each sell-out generates about $700,000. Midler’s “The Showgirl Must Go On” and Cher have no comp tickets.

Cher’s opening stanza concluded Sunday and she resumes her residency Aug. 6, performing Tuesdays, Wednesdays and weekends through Oct. 5. As currently scheduled, Cher’s tally for the year will be 50 shows.

Midler is booked Tuesday through Sunday in June and July and for two weeks each in October, November and December. If no more shows are added or canceled, she will play 68 concerts in 2008.

Estimated grosses for the year would put Midler around $47 million and Cher at about $35 million, numbers that collectively would top Celine Dion’s highest-grossing year, 2005, during which the box office took in $81.3 million on about 160 shows.

Cher is booked for 200 shows over three years while Midler will do 200 by February 2010.

The third piece in the Colosseum puzzle remains Elton John’s “The Red Piano,” which is booked for a dozen dates in June, eight shows between July 23 and Aug.2 and 13 concerts from Oct. 22 to Nov. 9. John does about 50 dates per year at the Colosseum.

If concert figures hold steady from last year, it is quite possible that four acts that earn the bulk of their coin from a single Vegas venue will be in the year’s top 20 in grosses: Midler, John, Cher and Barry Manilow, who has 35 more dates booked this year at the Las Vegas Hilton.

Dion was consistently in the top 10 during her four years and eight months at the Colosseum. Dion performed 717 concerts and grossed $400 million in ticket sales. Intriguingly, in Dion’s first year at the Colosseum, 2003, she grossed $80.5 million and was the second-highest concert earner of the year. Right behind her was Cher at $68.2 million.

Related Review: Cher at the Colosseum, Caesars Palace, Las Vegas