SOMEONE named David will be the next "American Idol." The only question is whether it'll be rocker David Cook or tween heartthrob David Archuleta - the final two singers left standing on Fox's megahit talent show. Pretty songbird Syesha Mercado got the boot last night, setting up the all-David "Idol" finale next week. Mercado, 21, of Sarasota, Fla., had been the last woman standing. Next week's finale will be the first guy vs. guy title bout since Ruben Studdard edged now-"Spamalot" star Clay Aiken in the show's second season. "Idol" fans cast more than 56 million votes by phone and text messages on Tuesday night, host Ryan Seacrest said. Judge Simon Cowell talked up next week's finale with old-school hype. "I think we're going to have a real humdinger," said the acerbic British judge, drawing good-natured taunts from the crowd for his old-fashioned choice of words. Archuleta, 17, had been considered the early favorite, captivating audiences with his smooth, wise-before-his-years sound. Fans also have warmed to his innocent demeanor and his triumph over a paralyzing vocal-cord condition. In the past month, though, Cook, 25, appears to have grabbed the momentum with his creative rock melodies. Judges have praised Cook for giving a personal spin to several well-known tunes. "He's gotten great traction out of making his own arrangements," said James Hellriegel, who runs the Dial Idol Web site, which traces voting patterns.  "At the same time, David Archuleta has been doing the same songs every week. He's been singing them great, but it's been the same." Although "Idol" doesn't disclose vote totals, Dial Idol tracks the frequency of telephone busy signals - a possible measure of voting popularity. Archuleta topped his rivals in the rounds of 12, 11, 9 and 8, according to Dial Idol. But Cook has been the No. 1 "Idol" in the rounds of 10, 7, 6, 4 and this week's round of 3, the Web site reported. "He [Cook] is the favorite, but I don't feel comfortable saying he's going to win," said Maria Milito, a classic rock DJ on 104.3 FM and regular "Idol" watcher. "I don't trust America." Both "Idol" finalists have faced considerable off-stage distractions this season. Archuleta's father, Jeff, was booted from rehearsals by producers for his alleged stage-dad behavior. Last month, Cook dedicated his take on Mariah Carey's "You Will Always Be My Baby" to his cancer-stricken brother.              - New York Post