This is a rendering of what the Purple Line station would look liike in Riverdale Park. Unlike most other Purple Line stations, this platform would be elevated. (Maryland Transit Administration)

Gov. Larry Hogan’s imminent choice about the Purple Line will play a large role in defining whether his first year in office steers his Maryland Republican Party toward the middle or gives Democrats a cudgel to beat him as an anti-spending ideologue.

In nearly five months of studying the light-rail line, Hogan has impressed observers with his willingness to consider building it even though he said flatly during last year’s gubernatorial campaign that Maryland “simply cannot afford this project right now.”

The governor’s openness partly reflects his desire to project an image as a pragmatic steward who does what’s best for the state rather than a knee-jerk conservative as Democrats would like to portray him, analysts said.

Hogan also may be showing unexpected interest in the 16-mile link between Bethesda in Montgomery County and New Carrollton in Prince George’s County because of the overwhelming support it enjoys from Washington-area business leaders, including some Republicans. Top local executives of 19 major companies — including Verizon, Geico and Capital One bank — sent Hogan a letter Thursday backing the Purple Line.

But Hogan’s continuing doubts about the project’s cost and benefits show he still shares some anti-transit views that he and his conservative supporters have long championed. He has repeatedly expressed disbelief in projections that the project would generate tens of thousands of jobs. He has said Maryland needs to shift spending from mass transit to roads and bridges.

Interactive map of the proposed Purple Line in Maryland with stations and controversies along the way.

So Hogan’s decision not only will make or break the rail line, which is being overseen by the Maryland Transit Administration, but also will be his first big administration-defining choice.

Although Hogan insists he can support mass transit if the price is right, he was active in the past in groups that routinely decried such infrastructure spending as boondoggles.

The governor is a former director of the Maryland Public Policy Institute, a Rockville-based think tank whose president says light-rail projects such as the Purple Line are never justified economically. Hogan also founded the grass-roots group Change Maryland, which strongly denounced what it saw as excessive government spending.

Purple Line supporters worry that such a background prevents Hogan from seeing the potential benefits of public investment in transportation.

Tom Bozzuto, chief executive of a regional development company based in Greenbelt, said he viewed Hogan as “a man of integrity” who was making an honest assessment of the project. But Bozzuto worried that Hogan’s reservations about the Purple Line are short-sighted.

“People like Hogan get tripped up because he sees, as most business people see, that our government has spent more money than it’s taken in, and the economy of Maryland hasn’t benefited,” Bozzuto said.

“It becomes too easy to move from that to the conclusion that all spending is bad, without recognizing the value of investment spending,” he said. Bozzuto, who called himself “a conservative Democrat,” is interested in investing along the Purple Line’s route but does not own land there.

It’s hard to overestimate how much the Purple Line decision will shape perceptions of Hogan’s first year in office. After defying the odds to win the governorship in an overwhelmingly Democratic state, his biggest political challenge has been to tug Maryland to the right on spending and taxes without alienating voters who have supported activist government.

In his first General Assembly session earlier this year, Hogan succeeded in restraining spending modestly without setting off too many partisan fireworks. He also won praise overall for his role in handling the Baltimore riots in April.

But it will be hard to avoid offending someone with a decision as large as the Purple Line.

If Hogan kills it, he risks giving up the GOP’s chances to make inroads among independents and conservative Democrats in Montgomery County. It is the state’s biggest jurisdiction and one of only four in the state that Hogan did not win in November.

Hogan also would be vulnerable to criticism that he gave up $900 million in federal funding recommended for the Purple Line — money that wouldn’t come to Maryland if the project dies.

If Hogan builds it, however, he alienates voters in rural areas and outer suburbs who think the state already does too much for the Washington suburbs. They voted overwhelmingly for Hogan and crave increased spending for their roads and bridges.

Then there’s the outstanding question of the Red Line, a proposed light-rail project in Baltimore that would cost even more than the Purple Line. If Hogan approved the Purple Line, there would be little money left over for the Red Line.

Two recent developments have increased the political challenge for Hogan. It emerged Wednesday that Transportation Secretary Pete K. Rahn has endorsed building the project, providing that its $2.45 billion cost is reduced and Montgomery and Prince George’s counties kick in more money.

(Rahn’s action was disclosed by two officials who spoke on the condition of anonymity. The governor’s office neither confirmed nor denied the report but suggested it might not be Rahn’s “final” recommendation.)

State politicians and commentators said Rahn’s move had put Hogan in a box.

“If Hogan moves forward with the project, he looks weak and pushed into it by Rahn, despite the strong opposition of many Republicans,” American University government professor David Lublin, a vocal critic of the Purple Line, wrote in his blog, Seventh State. “If Hogan nixes it, he looks like he has ignored the advice of the Secretary he charged with it and transit advocates will beat him over the head about it.”

In addition, Hogan seemed to have forgotten his anti-spending philosophy during a recent trip to Japan, when he expressed enthusiasm for a high-tech, magnetic levitation (maglev) train that he rode there. He said he will request a $28 million federal grant to study building such a train between Washington and Baltimore, a link that would cost at least $10 billion.

In response, the pro-transit blog Greater Greater Washington wrote a teasing headline: “Maryland’s governor thinks the Purple Line is too expensive, but wants to build a $10 billion maglev. Huh?”

Hogan spokesman Doug Mayer said the two projects were “apples and oranges” because the state hasn’t been asked to spend money on a maglev train.

Hogan said a month ago that the Purple Line’s estimated cost of $153 million per mile was “not acceptable” and would have to be “dramatically lower” to win approval.

Supporters say the line is vital to connect the Metrorail system with Amtrak and MARC commuter lines, and to link job centers such as Silver Spring and Bethesda with the University of Maryland and other neighborhoods. They say it would focus growth, attract jobs and rejuvenate aging suburbs.

Defenders also noted that the price is lower than the cost of comparable projects elsewhere. According to the Transport Politic blog, the cost per mile for light-rail projects in Portland, Ore., Los Angeles and Boston ranges from $205 million to $302 million.

In addition, the Purple Line gets a “medium-high” rating for cost-effectiveness from the Federal Transit Administration. Of seven major light-rail projects around the country in the same stage of development, only one other project, in Denver, gets such a high rating.

None of that impresses some Purple Line critics, who say the federal standards are biased in favor of light-rail.

“Light rail is just not a cost-effective mode of transportation,” said Christopher B. Summers, president of the Maryland Public Policy Institute. “Rapid bus is a much more cost-effective way to go.”

Hogan was a director of the free-market-oriented institute from 2011 to 2013. He “has a very intimate knowledge of the institute’s work,” Summers said, and the group provided much of its work to the governor’s transition team.

The governor’s office said Friday that Hogan still has not made a decision but plans to do so by the end of June. Although his staff was tight-lipped about the discussions, it seemed clear the project would win approval only if it is scaled back considerably.

A Republican who occasionally advises Hogan, and who spoke on the condition of anonymity to be candid, predicted that the project was dead: “He’s not going to build it, unless something changes. The numbers just don’t work.”