Here is what we've learned about some of those rumors.
Rosenfels has two years remaining on his contract, which calls for a base salary of $1.35 million in 2008 and 2009 and a cap hit of $1.85 million in each of those years with $500,000 in prorated bonus money in each year.
In 2007, Rosenfels completed 154 of 240 passes for 1,684 yards, 15 touchdowns and 12 interceptions for an 84.8 passer rating. It was by far the most extensive action of his career.
Lemon's agent confirmed the Vikings' interest in him but said it was hard to gauge their interest compared to other teams that were expected to make offers. The New York Giants and Jacksonville Jaguars are showing interest in him, and he is scheduled to visit with the Jaguars tomorrow. The Vikings hadn't made an offer within an hour of free agency opening.
Lemon also received the most extensive action of his career last year, in his case with the Miami Dolphins. He completed 173 of 309 passes for 1,773 yards, six touchdowns and six interceptions for a 71.0 rating.
McCown's agent didn't return an e-mail seeking his comment.
Losman has played in 33 games the last three years with the Bills. For his career, he has completed 495 of 837 passes for 5,627 yards, 31 touchdowns and 29 interceptions for a 77.3 rating.
Another possibility if neither of them is signed is Raiders DE Tyler Brayton. Brayton has been moved between end and tackle since joining the Raiders in 2003, but he has played in all but one game in his five seasons in the NFL. During that time, he has totaled 140 tackles and six sacks. He currently has a visit set up with the Carolina Panthers, according to Caplan.