DURHAM, N.C. — Bill Clay drives a car that runs entirely on recycled vegetable oil, and prominently displays a "No Keystone XL" sign through the back window so drivers behind him can know exactly where he stands.

Clay, a North Carolina native, has been involved in Democratic politics for decades. He volunteers on campaigns and works as a progressive activist. He's also an active participant in the Moral Monday movement — the statehouse protests that have harnessed the progressive fury at the Republican-controlled legislature in North Carolina.

Like many progressives here, Clay isn't that impressed with the state's Democratic Sen. Kay Hagan, one of the most vulnerable senators in the country this year. He calls Democrats like Hagan "corporatists" and said he worked for Hagan's primary opponent Jim Neal in 2008, though he eventually volunteered for her.

"A lot of the progressive community, people that are focused on policy, aren't enthusiastic about Kay Hagan," Clay said. "But a lot of them are like me. I look at it like it's a pragmatic exercise: the lesser of two evils should result in less evil."

"She's better than the alternative," echoed Joshua Bradley, a member of the Wake County Progressive Democrats after a meeting in Raleigh. "I'm still probably going to wake up in the fetal position in the shower sobbing after I vote for her, but I'm going to vote for her."

People like Clay and Bradley — motivated, active Democratic voters — will be essential to Hagan this fall if she is going to hold onto her Senate seat. They believe most will eventually come around to support the moderate Hagan, not because she's especially inspiring, but because Democratic-controlled Senate could hang on the outcome of Hagan's race.

The frustration among some Democrats is real, though. While Hagan is essentially aligned with progressives against the state's conservative legislature, she remains elusive.

When Democrats gathered in Charlotte earlier this year for a state executive committee meeting, Minnesota Sen. Amy Klobuchar was there to meet with them — but Hagan didn't show.

"All the people there were telling us we had to vote for Kay Hagan and I'm thinking, This is disrespectful to the state party you want to be the Democratic nominee for," said Chris Telesca, president of the Wake County Progressive Democrats and an active member of the state Democratic Party.

"Amy Klobuchar was there telling us what a great friend Hagan was," he said. "Klobuchar was there and is a lot more progressive than Hagan, but Hagan wasn't there. "

Now that campaign season has picked up in earnest, Hagan has begun showing up at party county conventions to meet with activists and party officials. (A few said that was the first time they had actually seen her.) She held one public event during the first week of Easter recess, delivering a bronze star to the widow of a World War II veteran.

After the event, Hagan played it safe with reporters. Moral Monday participants are "showing their anger and frustration with the actions taken by the current general assembly which hurts North Carolina," she said.

"I go to work every day working for jobs and economic growth. People are worried about social security and Medicare," Hagan told reporters. "I put North Carolina first. And I contrast that with my opponents and they are putting the special interests first, particularly the Koch brothers."

Elected in the Obama wave of 2008, the moderate Hagan is staring down one of the toughest reelection bids in the country. Polling shows her neck and neck with several of the potential GOP contenders, including Thom Tillis, the speaker of the House who is backed by Karl Rove's American Crossroads and the NRA. Republicans in the state, which went red in 2010, have made unseating Hagan a priority since she won.

The good news for Hagan, Democrats in the state say, is that the sustained efforts of the Moral Monday movement will be a key factor in her race.

Primarily organized by the North Carolina NAACP, the Moral Monday movement now includes a broad array of progressive, liberal, and activist groups who have shown up to the statehouse week after week when the legislature is in session. The Monday protests grew out of the NAACP's annual "Historic Thousands on Jones Street" march, or HKonJ.

Rev. William Barber, president of the North Carolina NAACP and widely viewed as the leader of the movement, said that the Moral Monday movement stage was not for politicians and called the senate race "critical." They've organized 117 Moral Monday rallies around the state since the legislative session ended.

Now, however, the NAACP is working to building out the movement, creating coalitions with other groups, and sending organizers to parts of the state dominated by Republicans. While maintaining that the movement is "nonpartisan" — they do not officially endorse candidates — Barber said that it was still deeply political.

Some of the groups involved in those coalitions, like Planned Parenthood, are enthusiastically behind Hagan and have vowed to work for her. Planned Parenthood's action fund and their North Carolina affiliate have pledged a $3 million get-out-the-vote effort in targeted districts.

And talking to activists, that same thing comes up again and again: voter turnout. In addition to the Planned Parenthood efforts, the NAACP is engaged in an extensive voter registration operation in counties across the state. "The Senate race is critical and certainly we are going to mobilize to get out the vote, we're going to be mobilizing people to examine the candidates, and examine where they have stood on these issues of economic stability, education, and health care," Barber said. "Those are critical moral questions."

For their part, Hagan's campaign plans to build off of Organizing for Action's considerable data and voter identification work in the state. Morgan Jackson, a Democratic strategist in Raleigh, said that Hagan's campaign would have to, and is, appealing to a largely urban voter base and must "do her best to limit losses in rural areas."

"There is not one issue right now — an anti-war or something like that — that motivates everyone to turn out and vote in a low turnout election," Jackson said. He noted that Hagan has talked up issues that play to certain parts of the base, a clear nod to the Moral Monday movement. "Frankly, I'm one of those people who said 18 months ago, 'This is great but we are a long time from an election and can we sustain this?' What we've seen over the last 12 to 16 months is that it is being sustained, but it's not one issue."

If progressives haven't come home to her to yet, they will, the strategists say, especially if the Republican nominee ends up being Tillis. They argue Tillis' position in helping pass an array of laws (abortion restrictions, voter I.D. laws, and blocking Medicaid expansion to name a few) helped ignite the Moral Monday protests and those stances will help rally frustrated liberal blocks in places like Charlotte, Raleigh, and Durham.

"Look at what Thom Tillis, the speaker of the House has done," Jackson, the strategist, said. "It gives Hagan a great latitude. You aren't damping any of the outrage of the base, he is actually continuing to feed it. That's going to keep a lot of the energy alive."

"It's easy at this point to take it a little for granted and say yeah, 'I'm not with her' but the reality this fall, the rubber meets the road," Jackson said. "If nothing else, Tillis by himself is a motivator."

Washington Republicans remain enthusiastic about their chances to retire Hagan.

Outside groups like Americans for Prosperity have poured millions of dollars already into negative ads. If Tillis does end up as the nominee, Republicans aren't concerned yet that his tenure as speaker will weigh him down: A Republican source working to defeat Hagan told BuzzFeed that the National Republican Senatorial Committee had done several focus groups in North Carolina with independent and center-right women and found little controversy over the state legislature.

"The NRSC is neutral in the primary, but Thom Tillis has demonstrated that he is an effective leader capable of getting things done for his constituents, which is the exact opposite of Kay Hagan who has been an inept legislator and a rubber stamp for the Obama agenda even when North Carolinians disagree with it," said NRSC spokesman Brad Dayspring. "People are looking for competency, effectiveness, and someone who can get Washington working again. It's a simple fact that voters in North Carolina — Democrats, Independents and Republicans alike — have trouble naming a single accomplishment of Kay Hagan's."

If anyone's looking for clues on what the campaign against Hagan will look like: A spokesman for Tillis also dinged Hagan for "rubberstamping" President Obama's agenda. "We are happy to compare Thom Tillis' record of solving problems and tackling tough issues with Kay Hagan's record of rubberstamping the Obama/Reid agenda in Washington," campaign spokesman Jordan Shaw said.

The summer session is approaching at the state house — and Moral Monday will soon return. And the progressives who aren't Hagan's biggest fans are looking for a sign from her.

"I will undoubtedly vote for Kay Hagan, but I just wish she took more interest in the needs of the average North Carolinians than the needs of the establishment crowd," Telesca said.

Planned Parenthood of North Carolina's president Janet Colm, who was arrested last year during a Moral Monday protest, said that even skeptical Democrats in the state will come around to Hagan, if only to begin the long process of getting the legislature back and that Democrats needed to look at the long-term picture.

"The Hagan race is the key to take back the state," she said. "If we win this race, which is independent of redistricting, then in 2016 we have a gubernatorial race, which is independent of redistricting, so if we can begin to show that we can win some of these statewide races and eat away what's happening in the legislature, our goal is by 2020 to have one house of the legislature."

"It's not a quick thing, but Hagan is the key. It's the opening; this race is not just about her."