(CNN) - The spotlight will shine on the 2014 and 2016 elections as some 3,000 activists from the left gather in Detroit starting Thursday.
That's when the annual Netroots Nation conference, the largest gathering of progressive leaders and activists, kicks off. And two of the Democratic Party's biggest stars - Vice President Joe Biden and freshman Sen. Elizabeth Warren of Massachusetts - will give keynote addresses.
While the 2016 race for the White House will be a topic of discussion in dozens of panel discussions, the more immediate concern is this November's midterm elections and Democrats trying to hold onto control of the Senate.
The smaller, typical midterm electorate traditionally favors the Republican Party because single women and younger and minority voters - big supporters of Democrats in presidential election years - tend to cast ballots in smaller numbers in the midterms.
Putting a strategy together to motivate those on the left to show up at the polls come November is on the to-do list at the Detroit gathering.
"A large number of people at our conference are the people that are going to be knocking on doors and making phone calls, and that's often is something that doesn't happen during midterms. Certainly some of the demographics here is exactly the demographics they want turning out: young and people of color and women," Raven Brooks, executive director of Netroots Foundation and Netroots Nation, told CNN.
"An even bigger part is the reach and influence that all of the people here have," Brooks added. "It's important to get them energized and activated so they can then go back to wherever they live and energize their local community."
Progressives are a key constituency in the Democratic Party, a major drawing card for Netroots Nation.
"The folks that are coming, such as Sen. Elizabeth Warren and Vice President Joe Biden, recognize the power of this community and they know this is an election that people have to turn out for if we're going to win," Brooks said.
Biden, Warren, and Clinton
Biden has been a tireless campaigner for his party, but he's also had to balance his own aspirations, which might include another bid for the White House. That makes his first-ever appearance at the annual gathering all the more intriguing.
Both Biden and Warren spoke Wednesday in Washington at the Make Progress National Summit, a gathering of young progressives.
"I'd like to think I did my part for marriage equality," the vice president said in his speech, touting his early support - even before President Barack Obama - for legalizing same sex marriage.
But Biden may have a tough time winning the support of some on the left if he does decide to launch a 2016 presidential campaign.
"There's a lot of good will towards Joe Biden and respect for his legacy," said Adam Green, the founder of the Progressive Change Campaign Committee, a group that strongly supports Warren and boasts an email list of nearly a million people.
But Green went on to tell CNN that "Someone who's been in the Senate and White House for around 40 years probably is not best equipped to have their finger on the pulse of the rising economic populist tide in America. I think there's going to be a search for some fresher voices and people more looped into our movement."
Warren has been traveling the campaign trail the past couple of months, in support of fellow Democrats running in 2014. But she's said numerous times that she's not running for the White House in 2016. But that didn't stop a group titled "Ready for Warren" from launching a Facebook campaign and Twitter feed on the eve of the conference to try and convince Warren to change her mind.
The group plans to make a splash at the conference.
"At Netroots and beyond, we're going to show Warren what huge momentum she has if she were to jump into the race," Erica Sagrans, the group's campaign manager, told CNN.
And they'll find a very receptive crowd at Netroots.
"There's certainly a contingent that are hopeful and actively trying to do things to create the conditions to let her say yes to that," Brooks said.
Hillary Clinton, who is in the middle of a book tour for her new memoir "Hard Choices," isn't attending Netroots Nation. She was invited but Brooks said her team "declined is because she's not out on the political scene."
The former secretary of state's seriously considering another bid for the White House, and if she runs, as many expect she will, Clinton would instantly become the overwhelming front runner for the Democratic nomination. But she may not the overwhelming choice of many of those attending Netroots Nation.
"If you go back to the 2008 campaign, our group was pretty split between Clinton and Obama," Brooks said, referring to the historic battle between then-Sens. Clinton and Barack Obama for the Democratic presidential nomination.
Brooks added that when it comes to Clinton's standing among progressives, "I do feel like there is a lot of love, and detractors as well."
The PCCC's Green said that Clinton has a lot of questions to answer before those on the left will support her.
"Hillary Clinton has made her views on social policy and foreign policy well known, but hasn't yet addressed many core economic populism issues, such as Wall Street reform, expanding social security benefits, or reducing student debt. A lot of people want to assume good intentions when it comes her her, but have some very tough questions about whether she will stand with Elizabeth Warren on key economic populist issues," Green told CNN.
While Clinton won't be in Detroit, an outside group that's urging her to run in 2016 will be there in force. Several members of Ready for Hillary will be at the conference, holding a session on how grassroots activists have changed the political landscape, and hosting a party for Netroots Nation attendees.