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Zephyr Teachout is turning New York Gov. Andrew Cuomo's reelection race into a dogfight.

Teachout, a law professor who worked for Howard Dean's 2004 presidential campaign, has mounted a challenge to Cuomo from his left.

She's aggressively drawing attention to the failures of Cuomo's Moreland Commission - the anti-corruption panel that backed down after it began sniffing around organizations close to the governor, according to a New York Times report.

Cuomo, who faces a federal investigation into the panel's closure, has said his office only advised the commission and denied interference with any investigations.

While still a long shot with little name recognition, Teachout, 42, is picking up support by tapping into progressive discontent with Cuomo's economic positions.

After recently surviving Cuomo's attempt to get her thrown off the primary ballot, Teachout picked up the endorsement of the state's second-largest employee union Thursday, after the state teachers union snubbed Cuomo by not endorsing either candidate.

Despite Teachout's rising stock, Cuomo has kept silent on his primary opponent and ignored her calls for a debate. His campaign did not return a request for comment on Teachout's bid.

ABC News spoke to Teachout about her challenge to Cuomo, progressive politics and her thoughts on Cuomo's presidential chances. The following is a Q&A, edited for brevity.

A judge recently threw out Gov. Cuomo's legal challenge to your campaign, which argued you weren't a New York resident.

It turned into an incredible opportunity for us. It's basically a three-day ad paid for by the Andrew Cuomo campaign. I can't tell whether he's scared of a primary, which it seems like he certainly acting like he is.

The governor is afraid of you?

It's the only logical explanation. It really doesn't make any sense. The rules are clear. You have to live somewhere for five years. I was there for five years. [A Vermont native, Teachout has worked at Fordham University since June 2009.]

One explanation is that it was a fishing expedition. Another is that he was trying to drain me of money, which backfired, because we've raised a lot of money on the court case - I'm truly estimating, but between $70,000 and $100,000.

I'll put this in a broader context. For years, Gov. Cuomo has managed to keep in control of politics, and now, there are things outside of his control, like what's happened with the Moreland Commission. You can't shut down a primary the way you can shut down the Moreland Commission.

You've made the Moreland Commission a big part of your campaign.

The [New York Times] report was eye-opening and scalding. It showed that his top aide was attempting to direct the activities of the commission. That kind of disrespect for the idea of law was really audacious.

Four years ago, you supported Cuomo's initial bid, and considered working for his campaign.

I think I had an experience similar to a lot of New Yorkers. I really admired his dad [former New York Gov. Mario Cuomo] and I saw him as a real moral force in politics.

But he basically hasn't been a Democrat! There are a lot of things that Gov. Cuomo does that doesn't make sense in terms of state politics.

Do you consider yourself a progressive in the same vein of New York City Mayor Bill DeBlasio?

Well, I am a progressive, but I am a down-the-line, traditional Democrat. I would be right at home in Mario Cuomo's cabinet.

But the support for DiBlasio is the same kind of support we're seeing. That hunger, talking about economic inequality and addressing the root issues of it.

Has he supported your campaign?

He supports the governor. In New York, we have a really powerful governor who uses his budgetary power to punish and reward.

It's very hard for politicians, without hurting their own constituents, to support a challenger to the governor. I'm not talking about DiBlasio, in particular, but more broadly. But there are an increasing number of brave individuals who are joining us.

How did working for the Howard Dean campaign prepare you for this race?

The heart of the campaign, as much as we touted our technical prowess, was the trust of the people. And the heart of this campaign is the trust of New Yorkers and New York Democrats.

For all the technological advances, there are still relatively few campaigns that really tap into the deep grassroots power that's there.

By most measures, you're still considered a long shot.

We're very focused on the voters most likely to vote. In New York, there's an extraordinarily powerful anti-fracking movement. There's a powerful parent and teachers movement that has been bird-dogging Cuomo across the state.

There's a lot of anger on Cuomo's silence on the national immigration crisis. New York hasn't taken leadership, and that's the role New York has traditionally played.

There are these real pockets of intense anger, and that's what matters in primary races: intensity.

What are your thoughts on the presidential chatter surrounding Cuomo?

I can tell you, from running against him, that Andrew Cuomo will not be president of the United States.

He's made some junior-league mistakes running against a relative unknown, and it's going to be hard for him to run for president after he's been defeated in the Democratic primary.