Who's got it better than the 49ers? That is, who's got a better record than their 6-1 mark?

The answer: nobody ... except for the undefeated Green Bay Packers.

The 49ers' lead in the NFC West grew to four games and their win streak climbed to five Sunday, courtesy of a 20-10 home win over the Cleveland Browns.

"It's fun. We're almost at the halfway point, and we've got a decent thing going on," defensive end Justin Smith said. "We've got to continue it, and we have a long grind ahead of us."

The 49ers will put their 3-0 road record on the line next Sunday when they visit the Washington Redskins, who are on a three-game losing streak. The Redskins (3-4) were shut out 23-0 by Buffalo on Sunday in Toronto.

As the 49ers, now at 6-1 for the first time since 1998, emerged from their bye week in winning style, their closest division foes fell further back in the standings. The Seattle Seahawks (2-5) and Arizona Cardinals (1-6) both lost, and the St. Louis Rams (1-6) notched their first victory.

"You can just feel it. The guys are pumped," quarterback Alex Smith said. "It's fun. It's fun to be on a roll. This is why you play. This is why you put in all the time (and) sacrifice, to get the 'W.' "

The 49ers raced to a 17-0 lead Sunday, sputtered for a while and finally outlasted the Browns (3-4).

Like so many other victories this season, Sunday's was keyed by a turnover-free offense, steady special teams and, of course, a physical defense.

From Ahmad Brooks' fumble-forcing sack on the Browns' first series to Patrick Willis' sack on the Browns' final possession, the 49ers defense was a menace. Cleveland's lone touchdown came on a 45-yard catch by Josh Cribbs from Colt McCoy with 6:17 remaining.

"Look up and down the defensive roster, and you see them come off the field, and they're just pouring everything out of their bucket," coach Jim Harbaugh said.

Offensively, it was a milestone day for running back Frank Gore. He passed Roger Craig to become the 49ers' second all-time leading rusher behind the late Joe Perry.

Gore matched a career-high with 31 carries, totaling 134 yards. It was the fourth consecutive game he's run for a touchdown and eclipsed the 100-yard mark -- the longest such streaks of his seven-year NFL career.

But Gore had to share the offensive spotlight with two unlikely heroes: linemen Joe Staley and Isaac Sopoaga, who recorded their first career receptions to set up field goals.

Staley slid out from his left-tackle spot to make a 17-yard catch in the first quarter. "Joe's very athletic," Harbaugh said.

Sopoaga, the starting nose tackle who's made cameos as a blocking back, hauled in an 18-yard reception on third-and-3 in the 49ers' final series, which yielded a 26-yard insurance field goal from David Akers.

As for the rest of the 49ers' passing attack, Smith missed an open Michael Crabtree on a few deep throws, but they did hook up for a 2-yard touchdown pass that gave the 49ers a 17-0 lead 1:31 before halftime.

Braylon Edwards had four catches for 42 yards in his first game since injuring his knee Sept. 18 in the 49ers' lone loss this season, an overtime decision against Dallas.

"I know we're not throwing the ball as much, but, at the end of the day, we're 6-1," tight end Vernon Davis said. "No one's pouting. Everybody's just high in character. We can move on and live with it. It's OK. We'll see better days."

Davis injured his right arm after making one of his three catches (for 27 yards) and said the pain was "killing me" as he finished out the game.

Once the clock ran out after a Browns reception at the 49ers' 18-yard line, Harbaugh and the 49ers' made a calmer exit than their last win at Detroit.

"Wins are beautiful things," Harbaugh said. "Guys are working hard for it and earned it. ... Not perfect, but beautiful. I'll take it."

For more on the 49ers, see Cam Inman's Hot Read blog at blogs.mercurynews.com/49ers.