After a sluggish start, Northstar is finally showing signs of finding its stride.

New numbers out on the state’s only commuter-rail line show a 15 percent increase in ridership six months into 2013 compared with the same time last year, according to Metro Transit. While still not quite hitting initial performance projections, the jump is by far the biggest the 40-mile line has seen since it opened in 2009.

Even critics welcome the news, saying sustained growth in ridership will help reduce taxpayers’ load in supporting a system that some argue should never have been built.

This spring was a season of firsts for Northstar. In April, the line exceeded 2,800 average weekday rides for the first time, and then pushed above 2,900 in May. In June, it surpassed 3,000, the figure it was projected to average at the onset.

Year to date, that figure is hovering at 2,700, according to data tracked by Metro Transit, operator of the line.

The gains come after ridership dropped slightly in 2012, following a slow start to its first two years of operations.

“It looks like the trend is finally there,” said John Siqveland, spokesman for Metro Transit. “I’d say the future is looking quite bright for Northstar.”

The increase is due largely to the opening of a station in Ramsey, combined with a $1 fare reduction made permanent in May, Siqveland said.

Special-event rides also have ratcheted up. Instead of rides to only select Twins and Vikings games, the line now serves all of them. And some 2,000 fans rode the line to a recent Kenny Chesney concert.

Such trips expose new people to commuter rail — and they might remember it next time they need to get from their house in Big Lake to their job in Minneapolis during a snowstorm, Siqveland said.

It takes about 50 minutes to travel from Big Lake — the farthest-north stop on the line — to Target Field in Minneapolis, with stops in Elk River, Ramsey, Anoka, Coon Rapids and Fridley.

“Ninety-seven percent of our trips are on time, rain, sleet or snow. That’s a very convenient option for people,” Siqveland said. “We just need to get people to realize that option is there.”

Increased marketing efforts are critical, said Leigh Lenzmeier, a Stearns County commissioner and chair of the Northstar Corridor Development Authority.

“I think some of the folks that preceded me as chair thought they could ‘build it and they will come,’ but Northstar isn’t light rail,” Lenzmeier said. “This takes marketing and getting folks used to something like this.”

Efforts in St. Cloud have targeted college students, who have been increasingly riding the Northstar Link bus to connect with the rail system for travel to and from the Twin Cities, Lenzmeier said, noting that young riders will be critical to continued growth for Northstar.

Ridership must reach 4,000 average weekday rides before talk of extending the line to St. Cloud can be restarted.

The gains make it easier to make “lemonade out of lemons,” said Rhonda Sivarajah, chair of the Anoka County Board, who opposed the line from the start.

“We now have an obligation to try and bring that subsidy per rider down as much as possible. That’s the only thing we can do as a county board to try and improve what I think is kind of a bad situation,” she said.

The subsidy per passenger climbed in Northstar’s first three years from about $18.70 to $19.50, according to Metro Transit. Costs also climbed for the line.

Though figures have yet to be calculated for 2013, the jump in ridership is expected to bring the subsidy down for the first time this year, said Drew Kerr, another spokesman for Metro Transit.

Comparatively, the subsidy for a public bus is $2.42 per passenger, though Kerr points out that commuter rail is a different service with longer routes, so subsidies aren’t expected to be the same.

To draw more riders, plans call for adding Wi-Fi to one car per train by the end of the year and offering a park-and-ride lot in Fridley that will link to Northstar and take riders to the State Fair.

By mid-2014, Northstar riders can also hook up to the Green Line light-rail line at Target Field and reach downtown St. Paul and the University of Minnesota.

The line still has a long way to go before it proves to be a worthwhile investment, said Matt Look, another Anoka County commissioner and chair of its regional rail authority.

“To really make sense you really need to get to that 10,000- ride mark; that’s when you’ll get closer to that $5 subsidy level,” Look said. “It will never make money, but if you can get 10,000 (vehicles) off (U.S.) 10, that’s a pretty good accomplishment. It’s fantastic to finally be heading in that direction.”