A town-hall spectator who elicited a headline-making non-answer from Hillary Clinton understands perfectly well why she dodged his question about Keystone XL.

He understands the pipeline represents a political predicament for the Democratic front-runner.

"There's enormous pressure from both sides," said Bruce Blodgett, a New Hampshire software developer whose question to Clinton produced news Tuesday across the U.S. and beyond.

"Any way she answers the question she'll alienate a huge number of people who could vote for her.... I completely understand why politicians try their best not to (answer questions). I'm not that naive."

But he adds that doesn't make it right.

The New Hampshire man is one of many people expressing frustration with Clinton this week, as people on both sides of the pipeline debate urge her to take a stand as the issue enters a critical phase.

Decision next month?

With a decision on the Canada-Texas project expected by President Barack Obama as early as next month, Clinton is being pressed from the political left and right.

Blodgett is a conservative who tries to attend as many political events as he can and says he considers himself lucky to live in an early primary state that hosts so many visiting politicians.

He said he was snapping a photo of Clinton during this week's event in Nashua, N.H., and happened to be near a microphone when it was free, so he seized the opportunity to ask a question.

He asked: "As president would you sign a bill — yes or no, please — in favour of allowing the Keystone XL pipeline?"

She replied that she couldn't answer because she'd been involved in the process when she was Secretary of State. She didn't want to second-guess the president in a process she'd been involved in.

Clinton then concluded with a tongue-in-cheek promise: "If it's undecided when I become president, I will answer your question," she said with a chuckle.

That opened the floodgates of frustration from left and right — not to mention from her questioner.

Frustration on both sides

"I tried my best not to give her any wiggle room. But she still found wiggle room," Blodgett said in an interview.

"It's never right for politicians to avoid answering yes-no questions, in a public town-hall meeting. That's what it's there for ... That's the job of a politician."

Clinton's Republican opponents, united behind the project, blasted her failure to step up. After all, she'd appeared to voice her support for it years ago — before suddenly turning silent when the issue may be entering its final phase.

Jeb Bush tweeted: "The President has to make lots of tough calls. Supporting Keystone XL and North American energy security is an easy one."

The issue is a bit more complex for Democrats like Clinton. Her party is divided over the Alberta-to-Texas pipeline and she's standing right over that fault line between her party's activist grassroots and public opinion.

Polls have frequently shown that, among Americans with an opinion on the project, a majority support it. But Clinton isn't just vying for centrist voters. In the short term, she needs to win enough left-leaning voters to carry the primary, and then keep those voters motivated so they turn out on election day.

Many left-wing voters want her to oppose Keystone. Her evasiveness is already drawing their ire. A host on the left-leaning MSNBC network called Clinton's justification for silence, "hogwash," and one prominent pipeline-fighter agreed.

Obama to reject pipeline, says senator 

"It is hogwash," said Jane Kleeb, who helped organize Nebraska ranchers against the project. "Because she is talking about Benghazi and lots of other issues that she clearly handled when she was Secretary of State."

Clinton wasn't getting much praise from the mainstream media, either.

A Washington Post blog titled, "Hillary Clinton's ridiculous hedge on Keystone XL," said her logic made no sense and could be used to avoid taking a stand on any number of topics she discussed in Obama's cabinet.

It added that the whole point of elections is to have voters hear from candidates.

If Clinton is bracing for a safety raft to weather the current tempest, she might have reason to hope one is on the way.

Washington has been awash in rumours that a presidential decision is coming soon, which would allow Clinton to declare the matter closed. A pro-pipeline senator, North Dakota Republican John Hoeven, gave voice to them Tuesday.

He told the Senate that he'd heard President Barack Obama might reject the pipeline next month. The White House and State Department had no comment.