April 25, 2012 7:00 a.m. NEW YORK — The haul in free agency and through trades has strengthened the Broncos, Bills and Bears. Now comes the lifeblood of any NFL team: the draft.

Denver merely landed the best quarterback ever to hit free agency, Peyton Manning. Buffalo homed in on one player to be a difference maker, 2006 top overall draft pick Mario Williams, and signed him before his only visit to a team ended. Chicago dealt for the No. 1 receiver it lacked, getting Brandon Marshall, and bolstered its roster by signing running back Michael Bush and even a quality backup quarterback behind the injury-prone Jay Cutler in Jason Campbell.

Those moves make all three franchises, none of which had a winning record in 2011 — yes, we know, the Broncos won the pitiful AFC West at 8-8 — more viable contenders.

With Manning aboard, the Broncos are in a win-now mode.

“I think the bottom line is we want to do the best thing to surround him with a team that’s going to give him an opportunity to win,” Broncos boss John Elway said. “We want to come out of every draft ... with players that are impact players. As I said last year, you have a lot more misses in my mind when you draft to need, so we’re going to find the best players in positions of need, but also try to find those impact players that are going to come in and help us right away.

“We’re talking about now. Impact doesn’t necessarily mean a starter, but one that can come in and help us win.”

Unquestionably, Manning is the major addition, as influential a newcomer as you can get. Denver could use an upgrade at receiver, and the Broncos just might target one at No. 25 overall.

“If you look at where we were and where we are, the offensive mindset is a little bit different than it was. That is going to change the type of people that we are looking at offensively,” Elway said. “Defensively, nothing has changed other than the fact that we’ve gotten to know (defensive coordinator) Jack Del Rio and the type of people he likes and the style that he is going to play defensively.”

The style of defense in Buffalo will be aggressive, with Williams as the focal point. Coming off a torn chest muscle that cost him the final 11 games of last season, the defensive end/linebacker still got the biggest contract in NFL history for someone on that side of the ball: $100 million for six years, with $50 million guaranteed.

Bills general manager Buddy Nix, however, always has emphasized that building a competitive team is done through the draft, and there’s no shortcut to that approach. Nix’s goal from the beginning has been to compile experienced depth — through the draft.

“My point is we’ve said from Day 1 that if there’s a guy there that we think can make the difference we’ll be aggressive and go after the guy,” Nix said. “So this just plugs up a piece of the puzzle and he’ll get us over the hump. He’s a position of need that we were able to fill, but the same philosophy will hold through in the draft.

“I think it had a lot of impact on us really,” Nix added of putting Williams, end Mark Anderson (another free agency signing), and incumbent tackles Kyle Williams and Marcell Dareus together. “Therefore, we’re a little freer as far as who we pick (10th overall).”

Offensive line could be where the Bills go with that selection. It’s also what the Bears might address at 19th overall. They’ve already upgraded their receiving corps and depth in the backfield, and the defense is solid.

“We got better,” star linebacker Brian Urlacher said. “On paper we’re a better football team than we were last year at the end of the season, so I’m excited about that.”

And Chicago hasn’t even made a draft pick yet.

Free agency also strongly helped the Cowboys and Buccaneers retool weakened rosters, freeing them to concentrate on quality over need early in the draft. That most benefits Tampa Bay, which chooses fifth and could have available the top receiver (Oklahoma State’s Justin Blackmon), the best pass rusher (North Carolina’s Quinton Coples), most proficient running back (Alabama’s Trent Richardson) or a shutdown cornerback (LSU’s Morris Claiborne).

“I think there’s value throughout this draft that fits the needs of our team,” GM Mark Dominik said. “I don’t truly believe a draft board is ever really set. You’re always tweaking your board.”

Thanks to free agency, some teams don’t need to tweak too much.