It’s still a long time before the congressional midterm elections in November 2018. But a lot of candidates are already showing interest in running. And many of them are embracing an environmental message that, traditionally, has been kept on the sidelines.

Ask Derrick Crowe why he had jumped into the Democratic primary for District 21, which includes a big part of Austin, and he starts talking climate change right out of the gate.

“I have a 2-year-old son, his name's Henry, and he's never known a year that wasn’t the hottest year in [modern] history on the planet," he says, "and that alarms me."

Climate is front and center for other candidates in that crowded primary race and in other districts, too. That’s something different from most other years, says Cal Jillson, a professor of political science at Southern Methodist University.

“Climate change generally and the environment are background issues. They generally don’t motivate the vote for most people,” he says. “Although there is a green community that is deeply aware of it.”

What’s changed? Jillson says with a climate change skeptic in the White House and Republicans controlling both chambers of Congress, the "Democratic resistance" is motivated to get the party to stand against the Trump administration.

KUT's Mose Buchele reports

“It’s a motivating part of the Democratic resistance to motivate Democrats to stand against the Trump administration,” he says.

Climate will likely be an especially hot topic in the District 21 race. The reason? Lamar Smith, the congressman who has represented the district for decades.

Smith chairs the House Committee on Science, Space, and Technology. He has used that platform to challenge established climate science and scientists.

"Historically, he's been safe enough in his district that he could do that without thinking much about it,” Jillson says. But now that the district includes more of Democrat-leaning Austin and San Antonio, “you’ve got a lot of Democrats trying to get in a race.”

Crowe agrees that the congressman’s attitudes may be out of step with those of his constituents.

“Yale Climate Connections does polling on what different congressional districts think about climate change,” he says. “Seventy percent of people in this district believe in climate change, and 70 percent of people believe that scientists are to be trusted on this issue.”

Smith's office didn't respond to an email from KUT requesting comment, but Crowe and other candidates see that as an opening. That could mean a general election race where climate is featured prominently.