Casey and Cook started the third round at 6 under and a stroke up on Stallings, Donald and Im.
Like Straka, American Dahmen has yet to win on the Tour.
"Having won this, my mindset now is I have nothing to lose", Casey said. "Who is the obvious one?"
Aberdonian David Law, who got into the event through his win in the Vic Open earlier in the season, sits joint 67th on two over after a 74.
And that was good news for Casey?
He played Friday as though he wants those photos to stay there.
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She loved yoga and according to her mother, wanted to dedicate her life to helping others. "She lit up every room she entered". The student was described by Reik as a juvenile and released no further information, including the name.
Lahiri, who has played the event in the past, said, "It was a decent start on a fair but demanding Copperhead course".
He also pointed to Johnson being the favourite, at least in the eyes of thousands of fans on a warm, sun-filled day at Innisbrook, the kind of buzz it had past year when Tiger Woods played for the first time.
"Playing with Dustin is going to be very exciting", Casey said. "You look at my results versus Dustin's".
Seventy players made the cut at 1-over 143 or better.
Casey last year ended eight years without winning on the PGA Tour when he closed with a 65 and had to wait to see if Tiger Woods and Patrick Reed could catch him.
Casey was at 8-under 205.
Knox had one of the more entertaining rounds by making an albatross on the par-five 11th, after taking a double bogey two holes earlier. I played it well - I had three great birdie opportunities and just didn't make any of them. At the time, the hole-in-one tied Kokrak with Paul Casey for the lead at 7-under par with the Copperhead Course's infamous "Snake Pit" finishing stretch of holes awaiting.
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Doug Collins ripped apart plans by House Democrats to continue investigating President Donald Trump over allegations of collusion. It's now up to Attorney General Barr to decide which parts of Mueller's report will be made public.
Coming off a victory three weeks ago in Singapore, the top-ranked Park birdied five of the first six holes on her final nine.
Johnson blasted a "moon-ball" approach out of a fairway bunker on the closing hole to set up a curling, downhill 10-foot birdie putt to close the gap on Casey's lead.
"I don't know (how the birdie putt on 18 missed)".
On the next hole, a par 5 where he had to lay up from the rough, Johnson had a 104-yard wedge for his third shot that travelled only about 50 yards.
His only bogey came at 12 after finding a greenside bunker. Johnson hit a hard pitch from 73 yards to the right of the tree and let the hill bring it back to the green. He then rolled in another birdie on 15th from 22 feet.
"Makes up for the other two", he said, walking to the 15th tee.
"I'm in a good position. because this golf course, it's tough", Johnson said. "It was a good score".
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That marked growth of almost 50 percent for the service launched in 2008 by the major TV and film studios to compete with Netflix. The media-entertainment unit of Comcast, NBCUniversal has said it will launch an ad-supported streaming service in 2020.