DENVER - Sen. Joe Biden has no bounce, at least according to the Gallup Daily tracking polls. It's official: Sen. Barack Obama has received no bounce in voter support out of his selection of Sen. Joe Biden to be his vice presidential running mate. Gallup Poll Daily tracking from Aug. 23 to 25 -- the first three-day period falling entirely after Obama's Saturday morning vice presidential announcement -- shows 46 percent of national registered voters backing Sen. John McCain and 44 percent supporting Obama. This is not appreciably different from the previous week's standing for both candidates. This is the...